Seasonal affective symptoms in adults with residual attention-deficit hyperactivity disorder

Seasonal Affective Symptoms in Adults With Residual Attention-Deficit Hyperactivity Disorder

Robert D. Levitan, Umesh R. Jain, and Martin A. Katzman

There is evidence from clinical, epidemiological, and neuroimaging studies that attention-deficit hyperactivity disorder (ADHD) and seasonal affective disorder (SAD} may have several features in common. To assess seasonal affective symptoms in adults with ADHD, 115 individuals attending an adult ADHD clinic in Toronto, Ontario, Canada were asked to complete the Seasonal Pattern Assessment Questionnaire (SPAQ). From this clinic population of 115, a total of 56 completed SPAQs were returned. Assuming that all individuals failing to complete the SPAQ were nonseasonal and depending on which case-finding criteria

were used, the rate of SAD in the overall clinic sample was estimated at either 10.4% (Terman criteria) or 19.1% (criteria of Kasper et al.}. These prevalence rates are significantly greater than the rates reported in large population surveys at similar latitudes. There was an apparent relationship between female gender, impulsive-subtype ADHD, and seasonality. Future studies to examine whether core symptoms of ADHD fluctuate across the seasons and to assess the efficacy of light therapy in "seasonal" ADHD patients would be of great theoretical and clinical interest. Copyright © 1999 by W.B. Saunders Company

A TTENTION-DEFICIT hyperactivity disorder (ADHD), as described in DSM-IV, is the

most common psychiatric disorder of childhood, with a prevalence of 9% in boys and 3% in girls. 1 While it was previously thought that ADHD is solely a disorder of childhood and adolescence, more recent studies have shown that up to 70% of ADHD patients continue to have significant morbid- ity in adulthood. 2-3 While inattentiveness, impulsivity, and motor overactivity are the core symptoms of childhood ADHD, adults with ADHD often report the onset of mood symptoms as a reason for seeking psychiatric help. 4 The phenomenology and pathophysiology of mood disturbances in adults with residual ADHD are not well delineated, although preliminary evidence in adolescents suggests that bipolar-spectrum mood disorders may be relatively common in this population. 5-7 More study is needed to clarify further the clinical and theoretical implications of mood disturbances in adult ADHD.

We have noted in our respective clinics (U.R.J. heads the adult ADHD clinic and R.D.L. heads the seasonal affective disorder [SAD] clinic at the Centre for Addiction and Mental Health), that many patients with adult ADHD report marked seasonal changes in mood; conversely, many patients with SAD report ADHD-like symptoms. There are several findings from prior research that might explain such an overlap: (1) patients with ADHD and patients with SAD often exhibit bipolar- spectrum mood dysregulationS-9; (2) neuroimaging studies have shown striking similarities in ADHD and SAD, with decreased global metabolism and hypoactivity of areas related to attentional control particularly marked in both disordersl°-12; and (3) a

heightened sensitivity to stimuli from the physical environment is thought to play a key role in both ADHD 13,14 and SADS; personality styles that are congruent with this have also been described in both disorders. 15,16

The goal of this preliminary study was to assess seasonal affective symptoms in adults with ADHD. We present preliminary findings from a subgroup of 56 individuals recruited from a larger sample of 115 consecutive patients attending an adult ADHD clinic over a period of 11 months.

METHOD

Sample

All attendees of the adult ADHD clinic at the Clarke Institute must be physician-referred, and all present with an impairing symptom(s) of inattentiveness and/or impulsivity. The overall sample from which the study subjects were recruited consisted of 115 consecutive adult referrals aged 18 to 65 years who attended the clinic over a defined recruitment period of 11 months. All subjects provided informed consent for the study.

Diagnosis of Adult ADHD

Because the diagnostic criteria for adult ADHD are in rapid evolution, attendees of the clinic undergo a particularly thor- ough clinical and structured assessment to maximize homogene- ity of the group. Where possible, patients must meet previously established thresholds of psychopathology based on prior studies of adult ADHD. Details of the assessment in sequence are as follows.

From the Clarke Division of the Centre for Addiction and Mental Health and the Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.

Address reprint requests to Robert D. Levitan, M.D., % Clarke Division of CAMH, 250 College St, Room 1135, Toronto, Ontario, Canada M5T 1R8.

Copyright © 1999 by W.B. Saunders Company 0010-440X/99/4004-0008510.00/0

Comprehensive Psychiatry, Vol. 40, No. 4 (July/August), 1999: pp 261-267 261

262 LEVITAN, JAIN, AND KATZMAN

At the time of initial presentation to the clinic, it is first established that the patient's IQ is within the normal range based on the Wechsler Adult Intelligence Scale. 17 Patients are then administered a package of self-report questionnaires including the following:

1. Checklist of DSM-IV criteria 18 for inattentiveness (> six of nine items required) and hyperactivity/impulsivity (> six of nine items required) currently and before age 7. One must have fulfilled these criteria both before the age of 7 and currently to be diagnosed with adult ADHD. If a patient met criteria for both inattentiveness and hyperactivity-impulsivity, they were designated as "combined." For the current study, to simplify our analyses, the hyperactive/ impulsive and combined subtypes were grouped together (group 1, impulsive) and the "pure" inattentive subtype was designated as group 2; this strategy has been suggested by prior authors based on the unique importance of hyperactivity/impulsivity as a core symptom ofADHD (R. Barkley, personal communication, October 1997).

2. Brown Attention-Deficit Disorder Rating Scale. 19 This 40-item scale has five domains including affect, memory, effort, activation, and attention. A total score greater than 55 is required to establish probable ADHD.

3. Clarke Adult ADHD Scale. 2° This 140-item scale is a composite of factors drawn from numerous sources with the DSM-IV items added. A score greater than 200 is required for probable ADHD.

4. Wender Utah Rating Scale. 21 This 65-item, four-point rating scale is based on the patient's retrospective recall of childhood symptoms and is weighted to hyperactive/ impulsive symptoms. For the current study, group 1 but not group 2 subjects had to meet a threshold level greater than 46 on selected items 21 on this scale.

Following completion of these rating scales, patients under- went a two-part comprehensive psychiatric interview by U.R.J., who was blind to the results of the self-report questionnaires. In part 1, the patient was assessed based on clinical history and presentation. For part 2, a second interview was performed to review collateral information including school report cards and/or previous clinical evaluations. Based on this clinical interview, it was determined whether an ADHD diagnosis was applicable; if so, groups were designated (group 1 or group 2) and comorbid disorders were delineated. To maximize the reliability and validity of these evaluations, the interviews were witnessed behind a one-way mirror by independent raters who would confirm or deny the presence of adult ADHD, the subtype, and comorbid disorders.

Structured Clinical Interview for DSM-IV

The Structured Clinical Interview for DSM-IV (SCID) was administered to confirm the presence or absence of adult psychiatric disorders other than ADHD. To avoid the confounding effects of major depression on the diagnosis of adult ADHD, individuals with current major depression are not included in the adult ADHD research database; patients with past major depression are included. Dysthymic disorder is not an exclusion criterion for the clinic.

Final Determination of Adult ADHD

In summary, the final diagnosis of adult ADHD was based on a combination of (1) self-report questionnaires, (2) a clinical

assessment including collateral information, and (3) the SCID (to assess exclusionary criteria). For an individual to be included in the clinic, all three had to be consistent with a diagnosis of ADHD.

Assessment of Seasonality

The instrument used to assess seasonality was the Seasonal Pattern Assessment Questionnaire (SPAQ). 23 The SPAQ is a

self-report questionnaire developed as a screening tool for epidemiological studies of SAD. The first section of the SPAQ asks subjects to rate the severity of seasonal changes in sleep, mood, weight, energy, social activity, and appetite on a five- point scale (0, not at all; 4, extremely marked). A global seasonality score from 0 to 24 can then be calculated based on the sum of these scores. Further assessment of severity is obtained by asking whether the seasonal changes are a problem and, if so, to what degree. The pattern of seasonal change is determined by asking the subjects to note the months in which symptoms are most and least severe. Based on large-scale epidemiological studies, case-finding criteria for probable SAD have been established. 24,z5 According to Kasper et al.,24 individu-

als are considered SAD-positive if they have a global seasonality score of 10 or greater and report a problem with seasonal changes of "moderate" to "disabling" severity. Based on the more stringent criteria of Terman, 25 only respondents with a global seasonality score greater than 16.7, the mean score found in a sample of clinically diagnosed SAD patients, z5 are considered SAD-positive.

Sample Selection

Based on clinical observations that suggested a possible association between adult ADHD and SAD, an initial pilot project was performed in which nine adult ADHD patients reporting seasonality were administered both the SPAQ and a semistructured interview to assess seasonal affective changes. The next consecutive 26 patients attending the adult ADHD clinic, as well as the previous 80 attendees of the clinic, were subsequently asked to complete the SPAQ. The 26 patients recruited prospectively were administered the SPAQ at the time of initial presentation to the clinic. The 80 patients recruited retrospectively received the SPAQ by mail and were asked to return it, completed, in a self-addressed envelope. In this way, all attendees of the clinic over an l 1-month study period (N = 115) were given an opportunity to complete the SPAQ, including 35 recruited prospectively (nine plus 26) and 80 recruited retrospectively.

Statistics

To gain a rough estimate of the prevalence of SAD in the adult ADHD population in comparison to the general population, each subject was designated as SAD-positive or SAD-negative based on the previously established SPAQ criteria already described. 24,25 To obtain the most conservative estimates possible, all patients failing to complete the SPAQ were considered SPAQ-negative for this analysis. Rates of SAD in the general population were taken from two large epidemiological studies.

SEASONAL AFFECTIVE SYMPTOMS IN ADHD 263

The first, which used the less stringent criteria established by Kasper et al., included 416 individuals in Montgomery County, Maryland. 24 The second, which used the more stringent criteria developed by Terman, included 212 individuals in Manhattan, NY. 25 In each case, SAD rates were compared in the current sample and the corresponding population sample using the chi-square test (×2).

The second set of analyses in the current study examined whether gender and impulsivity are associated with seasonal mood change in the adult ADHD population. This strategy was based on (1) the higher rates of SAD known to occur in females compared with males, 8 (2) the importance of impulsivity in the classification of ADHD, and (3) the high rates of seasonal depression found in other disorders with marked impulsivity such as bulimia nervosa (BN). a6,27 Frequency data were analyzed using the X 2 test. Comparisons of mean values for continuous variables were analyzed using unpaired t tests. Nonparametfic tests were used for comparison of individual SPAQ items.

RESULTS

The total clinic population of individuals with adult ADHD who were asked to complete the SPAQ consisted of 115 patients, including 81 males and 34 females. All 35 subjects recruited prospectively completed the SPAQ as requested. Of 80 subjects recruited retrospectively (i.e., who were asked to return the completed SPAQ by mail), only 21 (26%) complied. The rate of return of completed SPAQs for the overall sample was thus 56 of 115 (49%), including 34 males and 22 females. Table 1 compares the 56 SPAQ completers with the 59 noncompleters with respect to demographics, ADHD subtypes, ADHD scale scores, and lifetime affective disorder diagnoses. There was a signifi- candy greater proportion of females in the SPAQ- completer group; all other measures were highly similar in the two groups.

Prevalence Estimates

Regarding the prevalence estimates of SAD, even when all 59 SPAQ noncompleters were consid-

ered nonseasonal, the rate of SAD based on the criteria of Kasper et al. was much greater in the current adult ADHD sample (22 of 115, 19.1%) versus the Montgomery County population sample 24 (21 of 416, 5.0%, × 2 = 24.01, df= 1, P < .001). Using the same conservative methodol- ogy, the rate of SAD based on Terman's SPAQ criteria was also much greater in the current ADHD sample (12 of 115, 10.4%) than in the Manhattan population sample 2s (five of 212, 2.4%, X 2 = 9.87, df = 1, P < .01).

Role of Gender and Impulsivity

Table 2 summarizes the demographic characteristics and self-report ADHD questionnaire scores of SPAQ completers by gender. Males were significantly older, whereas females had more negative life events before the age of 18. There were no differences in marital status across gender groups. There was a much higher frequency of impulsive- subtype ADHD in females (86%) versus males (41%). The mean total Brown and Wender ADHD Scale scores were not significantly different across the two genders, while the mean Clarke ADHD Scale score was significantly higher in females.

Considering only the 56 SPAQ completers, 59% of females and 26% of males met case-finding criteria for SAD based on the criteria of Kasper et al. (X 2 = 5.96, df = 1, P = .015). Using the stricter criteria proposed by Terman, 32% of females and 15% of males met case-finding criteria for SAD (×2 = 2.32, df= 1, P = .13).

The mean global seasonality score for the 56 SPAQ completers was 12.0 ___ 6.0 (mean ___ SD). The mean scores for the six individual SPAQ items were as follows: mood, 2.5 - 1.0; energy, 2.5 _+ 1.1; social activity, 1.9 + 1.3; sleep, 1.7 _+ 1.3; weight, 1.7 __+ 1.3; and appetite, 1.7 __+ 1.3. The

Table 1. Comparison of 56 SPAQ Completers and 59 Noncompleters on Key Demographic and Clinical Variables

Completers Noncompleters Variable (n - 56) (n = 59) Statistic df P

Female gender 22 (39.3%) 12 (20.3%) X 2 = 4.95 1 .03

Age (yr) 40.9 _+ 9.1 41.3 -+ 10.0 t = 0.22 113 NS

Impuls ive-subtype ADHD 33 (58.9%) 33 (55.9%) ×2 = 0.11 1 NS

Brown Scale score 79.2 _+ 16.4 81.8 _+ 19.7 t = 0.76 113 NS

Wender-Utah Scale score 57.5-+ 13.5 56.6-+ 16.7 t = - 0 .34 113 NS

Clarke ADHD Scale score 239.4 ~ 46.1 242.0 ~ 46.8 t = 0.30 113 NS

Li fet ime ma jo r depression-recurrent 5 (8.9%) 6 (10.2%) X 2 = 0.05 1 NS

Li fet ime b ipolar II d isorder 8 (14.2%) 6 (10.2%) X 2 = 0.46 1 NS

NOTE. Results are presented as the number and percent or the mean _+ SD.

Abbreviat ion: NS, nonsignif icant.

264 LEVITAN, JAIN, AND KATZMAN

Table 2. Demographics and ADHD Scale Scores for 56 SPAQ Completers, by Gender

Variable Males Females Statistic df P

Age (yr) 43.1 _+ 9.8 37.5 +_ 7.9 t = 2.26 54 .03

Current ly marr ied 63% 62% ;<2 = 0.01 1 NS

Life events <age 18 yr 8.1 _+ 4.5 12.0 -+ 7.5 t = - 2 .16 54 .04

Life events >age 18 yr 10.4 _+ 4.4 12.4 _+ 5.1 t = - 1 .53 54 NS

ADHD subtype

Hyperact ive/ impuls ive 41% 86% X 2 = 11.26 1 <.001

Inattentive 59% 14%

Brown Scale score 76.1 + 17.7 80.5 + 15.8 t = -0 .96 54 NS

Wender-Utah Scale score 56.4 _+ 14.4 57.7 _+ 14.5 t = -0 .33 54 NS

Clarke ADHD Scale score 230.2 _+ 47.9 256.1 -+ 4.9 t = -2 .01 54 .05

NOTE. Results are presented as the number and percent or the mean _+ SD.

Abbreviat ion: NS, nonsigni f icant.

order of ranking for these scores was identical to that found in a prior SPAQ study of individuals with SAD. 28 The proportion of individuals reported to "feel the worst" in a fall/winter month (i.e., October through March) was 89%.

Table 3 summarizes the SPAQ data by gender. Global seasonality scores were significantly higher in females. When the six individual items on the SPAQ were considered, significant differences across the two sexes were found only for seasonal changes in energy and social activity; in both cases, there were greater seasonal changes in females. A greater proportion of females than males reported that seasonal changes were a problem. There was also a trend for the seriousness of the problem to be greater in females.

DISCUSSION

The current study is the first to assess seasonal affective symptoms in adults with ADHD. While the high rate of SPAQ noncompletion limits inter-

pretation of the current data, even when all individuals falling to return the SPAQ were considered nonseasonal, the rate of SAD in the overall clinic sample was estimated at either 10.4% (Terman criteria) or 19.1% (Kasper et al. criteria). These rates are significantly greater than the 2.4% and 5.0% prevalence estimates (based on Terman and Kasper et al. criteria, respectively) reported in two large population surveys in centers within 5 ° lati- tude of Toronto. 24,25 The data suggest that female patients with impulsive-subtype adult ADHD are particularly prone to seasonality.

There are several findings from prior research that might explain a high rate of SAD in the adult ADHD population, particularly in women with impulsive characteristics. While depression in general has a female preponderance, this is particularly true for seasonal depression, 8 although the reason for this is unclear. Very high rates of SAD have been found in BN, 26,27 a disorder of young adult women characterized by a variety of impulsive behaviors. This, combined with the current find-

Table 3. Summary of SPAQ Data by Gender

Males Females Parameter (n = 34) (n = 22) Statistic df P

10.8 + 5.5 13.9 -+ 6.2 t = -1 .99 54 .05 Global seasonal i ty score (0-24)

Indiv idual SPAQ i tems (0-4)

Sleep

Mood

Weight

Energy

Social act ivi ty

Appet i te

Seasonal i ty as prob lemat ic

Severi ty of p rob lem (0-5, only i f present)

1.6 _+ 1.2 1,9 _+ 1.4 z = -0 .57 NS

2.4 +__ 0.9 2.8 _+ 1.0 z = -1 .78 .07

1.6 _+ 1.2 1.8 _+ 1.4 z = -0 .35 NS

2.1 _+ 1.1 3.0 -+ 0.9 z = -2 .75 .006

1.5 _+ 1.1 2.5 -+ 1.3 z = -2 .71 .007

1.5 _+ 1.2 2.0 +_ 1.3 z = -1 .47 NS

11/34 (32%) 15/22 (64%) ;<2 = 5.29 1 .02

2.6 _+ 0.7 3.1 -- 0.9 z = -1 .68 .09

NOTE. Results are presented as the number and percent or the mean +_ SD.

Abbreviat ion: NS, nonsignif icant.


ings, suggests that a shared biological diathesis might underlie the impulsivity and seasonal mood changes found in females with either BN or adult ADHD. Serotonin dysfunction has been strongly linked to depression, 29-31 impulsivity, 32-34 and seasonality, 35-37 and has been found to be abnormal in BN, 38,39 other impulse-spectrum disorders, 34,4°,41 and SAD. 42-44 The evidence for serotonergic dysfunction in ADHD is minimal, although studies thus far have not had a particular focus on gender effects and impulsivity. Pending future studies of this nature, other models to account for the clinical overlap of SAD and ADHD need to be considered.

Another possible mechanism linking ADHD and SAD might relate not only to serotonin, but to arousal mechanisms likely to involve several trans- mitter systems, including dopamine. One of the classic models of ADHD proposes that the impulsive subtype of this disorder, in particular, is mediated by a state of central underarousal. 13,14 Interestingly, recent neuroimaging studies have found global decreases in cerebral metabolism in ADHD, which might be consistent with such a model. 1°,u,45,46 Of particular interest given the current results, such findings have been much more pronounced in females than in males. 46,47 In addi-

tion, strikingly similar findings have been reported for SAD, 12 including not only a generalized decrease in cerebral metabolism as in ADHD, but also particularly low activity in brain areas relevant for sustained attention and behavioral inhibition, including the medial prefrontal cortex. This latter finding led Cohen et al. 12 to propose that in SAD, "the ability to pay attention to environmental cues and sustain goal-directed behavior is reduced." It has been proposed that dopaminergic transmission is abnormal in SAD, 47 which could contribute to both attentional problems and decreased goal-directed behavior. It is thus interesting to speculate whether "seasonal" ADHD patients might be in a state of chronic underarousal compounded by light-depriva- tion and a further decrease in arousal in the fall/winter months.

Future studies to assess the effectiveness of light therapy in seasonal ADHD patients would be of great theoretical and practical interest. It might be that light enhances arousal mechanisms, in part via a dopaminergic mechanism, as is the case with the psychostimulant medications used to treat ADHD.

The fact that SAD patients consume carbohydrates to alter short-term mood states 48 and experience enhanced arousal following high-carbohydrate meals 49 is reminiscent of addictive models of psychostimulant agents. The mechanism of bright- light therapy is poorly understood, and there has been a dearth of research to assess the possible stimulant effects of light in humans.

A number of limitations merit consideration. It may be that only individuals experiencing seasonal mood changes were motivated to return a completed SPAQ, which may have contributed to the low completion rates overall. This was taken into consideration in our prevalence estimates by desig- nating all noncompleters as SAD-negative. Further- more, completers and noncompleters were similar on all demographic and clinical measures other than the proportion of female subjects.

To avoid the confounding effects of major depression on the diagnosis of adult ADHD, individuals with current major depression are not included in the ADHD research database. If some of these individuals have major depression with a seasonal pattern, this would contribute to an underestimation of seasonality in the current sample. As diagnostic strategies to differentiate adult ADHD and major depression are refined over time, it may be feasible to include current major depression in future studies of this type.

The SPAQ itself has significant limitations in that it was designed as a screening tool to identify likely cases of SAD. Although it was not used in this pilot study, a structured clinical interview should be implemented to confirm a SAD diagnosis.

Notwithstanding these limitations, even using the most conservative estimates possible, very high rates of SAD were found in this adult ADHD population, particularly in females with impulsive characteristics. The overall pattern of seasonal symptom change was highly similar to that found in the SAD population. Future studies using a modified version of the SPAQ that can assess seasonal changes in core symptoms of ADHD would help to clarify which pathological mechanisms account for the overlap of these two disorders. Light-therapy trials in the adult ADHD population would also be of great theoretical and clinical interest.

266 LEVlTAN, JAIN, AND KATZMAN

REFERENCES

1. Szatmari P, Offord DR, Boyle MH. Ontario Child Health Study: prevalence of attention deficit disorder with hyperactivity. J Child Psychol Psychiatry 1989;30:219-230.

2. Weiss G. Followup studies on outcome of hyperactive children. Psychopharmacol Bull 1985;21:169-177.

3. Hechtman L. Long-term outcome in attention deficit hyperactivity disorder. Psychiatr Clin North Am 1992;1:553- 565.

4. Biederman J, Faraone SV, Spencer T, Wilens T, Norman D, Lapey KA, et al. Patterns of psychiatric comorbidity, cognition, and psychosocial functioning in adults with attention deficit disorder. Am J Psychiatry 1993;150:1792-1798.

5. Winokur G, Coryell W, Endicott J, Akiskal H. Further distinctions between manic-depressive illness (bipolar disorder) and primary depressive disorder (unipolar depression). Am J Psychiatry 1993;150:1176-1181.

6. West SA, McElroy SL, Strakowski SM, Keck PE, McCon- ville BJ. Attention deficit hyperactivity disorder in adolescent mania. Am J Psychiatry 1995;152:271-273.

7. Wozniack J, Biederman J, Kiely K, Ablon JS, Faraone SV, Mundy E, et al. Mania-like symptoms suggestive of childhood- onset bipolar disorder in clinically referred children. J Am Acad Child Adolesc Psychiatry 1995;34:867-876.

8. Rosenthal NE, Sack DA, Gillin JC, Lewy AJ, Goodwin FK, Davenport Y, et al. Seasonal affective disorder: a description of the syndrome and preliminary findings with light therapy. Arch Gen Psychiatry 1984;41:72-80.

9. Wirz-Justice A, Buchili C, Gran P, Kielholz P, Fich HU, Waggan B. Light treatment of seasonal affective disorder in Switzerland. Acta Psychiatr Scand 1986;16:733-737.

10. Zametkin AJ, Nordahl TE, Gross M, King AC, Semple WE, Rumsey J, et al. Cerebral glucose metabolism in adults with hyperactivity of childhood onset. N Engl J Med 1990;323: 1361-1366.

11. Amen DG, Carmichael BD. High-resolution brain SPECT imaging in ADHD. Ann Clin Psychiatry 1997;9:81-86.

12. Cohen RM, Gross M, Nordahl TE, Semple WE, Oren DA, Rosenthal NE. Preliminary data on the metabolic brain pattern of patients with seasonal affecffve disorder. Arch Gen Psychiatry 1992;49:545-552.

13. Laufer MW, Denhoff E, Solomons G. Hyperkinetic impulsive disorder in children's behavior problems. Psychosom Med 1957; 19:38-49.

14. Satterfield JH, Cantwell DP, Satterfield BT. Pathophysiol- ogy of the hyperactive child syndrome. Arch Gen Psychiatry 1974;31:839-844.

15. Bagby RM, Schuller DR, Levitt AJ, Joffe RT, Harkness KL. Seasonal and non-seasonal depression and the five-factor model of personality. J Affect Disord 1996;38:89-95.

16. Zovko E, Jain U, Spence W, Sunohara G, Barr C, Sandor P, et al. Temperament and character traits in attention-deficit disorder-residual type patients (ADD-RT). Presented at the 44th Annual Meeting of the American Academy of Child and Adolescent Psychiatry and 17th Annual Meeting of the Cana- dian Academy of Child Psychiatry; 1997 October 14-19; Toronto, Ontario, Canada.

17. Wechsler D. WAIS-R Manual. New York, NY: The Psychological Corp, 1981.

18. American Psychiatric Association. Diagnostic and Staffs-

tical Manual of Mental Disorders. Ed. 4. Washington, DC: American Psychiatric Association, 1994.

19. Brown TE. Brown ADD Scales. San Antonio, TX: The Psychological Corp, 1996.

20. Jain U. The Clarke Adult ADHD Scale. Toronto, Ontario, Canada: Clarke Institute of Psychiatry, 1995.

21. Ward MF, Wender PH, Reimherr FW. The Wender Utah Rating Scale: an aid in the retrospective diagnosis of childhood attention deficit hyperactivity disorder. Am J Psychiatry 1993; 150:885-890.

22. First MB, Spitzer RL, Gibbon M, Williams JBW. Struc- tured Interview for DSM-IV Axis I Disorders-Patient Edition. Version 2. New York, NY: New York State Psychiatric Institute, Biometric Research Department, 1995.

23. Rosenthal NE, Genhart M, Sack DA, Skwerer RG, Wehr TA. Seasonal affective disorder and its relevance for the understanding and treatment of bulimia. In: Hudson JI, Pope HGJ (eds): The Psychobiology of Bulimia. Washington, DC: American Psychiatric Association, 1987:205-228.

24. Kasper S, Wehr TA, Bartko JJ, Gaist PA, Rosenthal NE. Epidemiological findings of seasonal changes in mood and behaviour. Arch Gen Psychiatry 1989;46:823-832.

25. Terman M. On the question of mechanism in phototherapy for seasonal affective disorder: considerations of clinical efficacy and epidemiology. J Biol Rhythms 1988;3:155-172.

26. Blouin AG, Blouin JH, Aubin P, Carter J, Goldstein C, Boyer H, et al. Seasonal patterns of bulimia nervosa. Am J Psychiatry 1992;149:73-81.

27. Lam RW, Solyom L, Tompkins A. Seasonal mood symptoms in bulimia nervosa and seasonal affective disorder. Compr Psychiatry 1991;32:552-558.

28. Hardin TA, Wehr TA, Brewerton TD, Kasper S, Berrettini W, Rabkin J, et al. Evaluation of seasonality in six clinical populations and two normal populations. J Psychiatr Res 1991;25:75-87.

29. Meltzer HY, Arora RC, Baber R, Tricou BJ. Serotonin uptake in blood platelets of psychiatric patients. Arch Gen Psychiatry 1981;38:1322-1326.

30. Heninger GR, Charney DS, Sternberg DE. Serotonergic function in depression. Arch Gen Psychiatry 1984;41:398-402.

31. Cowen PJ, Charig EM. Neuroendocrine responses to intravenous tryptophan in major depression. Arch Gen Psychia- try 1987;44:958-966.

32. Brown GL, Ebert MH, Goyer PF, Jimerson DC, Klein WJ, Bunney WE, et al. Aggression, suicide and serotonin: relationship to CSF amine metabolites. Am J Psychiatry 1982; 139:741-746.

33. Linnoila M, Virkunnen M, Scheinin M, Nuutila A, Rimon R, Goodwin FK. Low cerebrospinal fluid 5-hydroxy-indolaeetic acid concentration differentiates impulsive from nonimpulsive violent behavior. Life Sci 1983;33:2609-2614.

34. Hollander E, Stein DJ, Decaria CM, Cohen L, Saoud JB, Skodol AE, et al. Serotonergic sensitivity in borderline personality disorder: preliminary findings. Am J Psychiatry 1994; 151:277- 280.

35. Carlsson A, Svennerhom L, Winblad B. Seasonal and circadian monoamine variations in human brain examined post mortem. Acta Psychiatr Scand Suppl 1980;280:75-83.

36. Brewerton TD, Berrettini WH, Nurnberger JI Jr, Linnoila M. Analysis of seasonal fluctuations of CSF monoamine metabo-


lites and neuropeptides in normal controls. Psychiatry Res 1988;23:257-265.

37. Lacoste V, Wirz-Justice A. Seasonal variation in normal subjects: an update of variables current in depression research. In: Rosenthal NE, Blehar MC (eds): Seasonal Affective Disor- ders and Phototherapy. New York, NY: Guilford, 1989:167-229.

38. Jimerson DC, Lesem MD, Kaye WH, Brewerton TD. Low serotonin and dopamine metabolite concentrations in cerebrospinal fluid from bulimic patients with frequent binge episodes. Arch Gen Psychiatry 1992;49:132-138.

39. Levitan RD, Kaplan AS, Joffe RT, Levitt AJ, Brown GM. Hormonal and subjective responses to intravenous m-chlorophenylpiperazine in bulimia nervosa. Arch Gen Psychiatry 1997;54:521-527.

40. Coccaro EF, Siever LJ, Owen KR, Davis KL. Serotonin in mood and personality disorders. In: Coccaro EF, Murphy DL (eds): Serotonin in Major Psychiatric Disorders. Washington, DC: American Psychiatric Association, 1990:71-97.

41. Ballenger JC, Goodwin FK, Major LF, Brown GL. Alcohol and central serotonin metabolism in man. Arch Gen Psychiatry 1976;36:224-227.

42. Lam RW, Zis AP, Grewal A, Delgado PL, Charney DS, Krystal JH. Effects of rapid tryptophan depletion in patients with seasonal affective disorder in remission after light therapy. Arch Gen Psychiatry 1996;53:41-44.

43. Schwartz PJ, Murphy DL, Wehr TA, Garcia-Borreguero

D, Oren DA, Moul DE, et al. Effects ofmeta-chlorophenylpiperazine infusions in patients with seasonal affective disorder. Arch Gen Psychiatry 1997;54:375-385.

44. Levitan RD, Kaplan AS, Brown GM, Vaccarino FJ, Kennedy SH, Levitt AJ, et al. Hormonal and subjective responses to intravenous m-chlorophenylpiperazine in women with seasonal affective disorder. Arch Gen Psychiatry 1998;55: 244-249.

45. Zametldn A J, Liebenauer LL, Fitzgerald GA, et al. Cerebral glucose metabolism in teenagers with attention deficit hyperactivity disorder. Arch Gen Psychiatry 1993;50:333-340.

46. Ernst M, Liebenauer LL, King AC, Fitzgerald GA, Cohen RM, Zametldn AJ. Reduced brain metabolism in hyperactive girls. J Am Acad Child Adolesc Psychiatry 1994;33:858- 868.

47. Partonen T. Dopamine and circadian rhythms in seasonal affective disorder. Med Hypotheses 1996;47:191 - 192.

48. Krauchi K, Reich S, Wirz-Justice A. Eating style in seasonal affective disorder: who will gain weight in winter? Compr Psychiatry 1997;38:80-87.

49. Rosenthal NE, Genhart M J, Caballero B, Jacobsen FM, Skewerer RG, Coursey RD, et al. Psychobiological effects of carbohydrate and protein-rich meals in patients with seasonal affective disorder and normal controls. Biol Psychiatry 1989;25: 1029-1040.

Documents

Seasonal affective symptoms in adults with residual attention-deficit hyperactivity disorder