Forbidden)Kingdom)Drishti)Expedition) Flag#93)Report) · Forbidden)Kingdom)Drishti)Expedition) Flag#93)Report) Kingdom)of)Mustang ... Cataract)in)Tibet)eye)study.)volume)107];)and)a)

Forbidden Kingdom Drishti Expedition Flag #93 Report

Kingdom of Mustang

Nepal 2011

An expedition gathering extensive epidemiological data while providing

humanitarian care in a remote and impoverished region of Nepal.

Scott W. Hamilton, MED ’82, Expedition Leader

Brief Description of Project: This was an expeditionary humanitarian medical project carried out in a remote mountainous region of northwest Nepal known as Mustang. The purpose of which was to provide general medical, eye care and vision improvement for the Nepalese and Tibetan villagers residing in that area, and to gather basic health data on this unique and highly dispersed population. There have been a number of studies of eye disease, including cataracts, among Tibetans and Nepalese including: the Tibetan Eye Survey of 1987 [see Archives of Ophthalmology, 1989 Age Related Cataract in Tibet eye study. volume 107]; and a study in American Journal of Epidemiology, 1983, volume 118, (Lawrence B. Brilliant et al. on cataract prevalence, sunlight and altitude). However, the populations surveyed by the above cited studies are sufficiently different -‐ living in less remote areas -‐ and at lower altitudes than the Mustang population. Previous scientific studies of ophthalmic disease in Tibet/Nepal/China/India have reported rates of diseases substantially above rates seen at lower altitudes with substantially less exposure to ultraviolet light. These findings are consistent with the biology and pathophysiology linked to development of cataracts. Research is lacking on rates of these conditions in the more remote populations living at higher altitudes. Nepal is among the poorest countries in the world, with tremendous needs in basic healthcare. More than 50,000 children die in Nepal each year, with malnutrition as the underlying cause for more than 60 per cent of these deaths. Half of the children in Nepal are underweight and three-‐fourths of the pregnant women are anemic. Maternal and neonatal mortality rates are unacceptably high. It is estimated that 80% of blindness in Nepal is avoidable, or curable. The vast majority of people in need of ophthalmic care reside in the remote areas like Mustang. The leading cause of blindness in Nepal is cataracts, followed by trachoma, and injuries. Cataracts affect primarily older individuals, but can be treated very cost effectively by surgery with IOC (intra-‐ocular lens) implant. There are also many, young and old, suffering from uncorrected refractive errors (nearsightedness, farsightedness, astigmatism) that can be easily and inexpensively corrected with eyeglasses. Our expedition team was in the field for the month of August 2011, and conducted 13 clinics in various villages in Mustang. Team members along with 400 kilos of medical supplies and equipment were transported via a twin engine Dornier aircraft from Pokhara, Nepal, to Jomson Village, thereafter by 4-‐wheel drive vehicle, by tractor, on foot, and horseback. Ponies and porters were used to transport supplies, as there are no roads in much of the region. Team members traversed the Kail Gandaki Gorge (deeper than the Grand Canyon) and then crossed two 13,000’ mountain passes on foot to reach the Tibetan Plateau area conducting eye-‐screening

camps in a series of villages followed by a 2-‐day cataract and eye surgery field clinic in Tsarang Village. This unique expedition included 18 Buddhist monks who volunteered to serve as tri-‐lingual translators and assistants throughout the expedition. Our expedition team would like to formally acknowledge the previous work done in Mustang by Dr. Geoff Tabin from the USA, and Dr. Sanduk Ruit from the Tilganga Eye Institute, Kathmandu, Nepal who performed eye screenings and cataract surgery in Mustang in 1994 and also in 2004. They also have a small eye clinic in Jomson, and conduct an annual cataract program in that location. Background: Mustang is a semi-‐autonomous “Forbidden Kingdom” of Western Nepal, and was only opened to outsiders in 1992. It remains a remote and little visited region requiring special permits to enter. Because of its isolation, it was protected from the Chinese invasion of Tibet and has remained largely Tibetan. The Dalai Lama has referred to Mustang as "one of the few places in the Himalaya region that has been able to retain its Tibetan culture unmolested". Drishti is a Sanskrit word meaning “vision” or “insight”, and is a good descriptive term for our expedition providing much needed eye and vision care to villagers living in the remote “Forbidden Kingdom” of Mustang, Nepal. The rural and highly dispersed population of Mustang is severely disadvantaged and underserved. Over 85% of the people belong to social groups classified by the Nepalese government as marginalized, disadvantaged, endangered, or Dalit (“Untouchable”). Life expectancy is only 57 years, and the literacy rate is 61% for men and just 41% for women. Children comprise about 28% of the population, and seniors 50 years and older, many of whom suffer from vision problems, make up another 18% of the total population of Mustang. Most of the inhabitants live at an altitude of between 11,000’ and 13,000’ above sea level. Solar radiation is intense, and the area is similar to a high altitude desert, with copious amounts of wind and dust. Access to healthcare is quite limited, and living conditions are well below Western standards. The population is highly dispersed, and in some cases nomadic. The primary occupation is subsistence agriculture. Population: A 2011 census by the Government of Nepal lists a population of 13,799 in the entire Mustang region. Our team examined and gathered data on 1,557 individuals or approximately 11% of the population. Language: The native language in the area is Tibetan, and many of the younger inhabitants also speak Nepali, both of which are written in a Sanskrit style. Our tri-‐lingual monk assistants translated this information to English for the purposes of filling out forms and recording data. This predictably resulted in spelling variations.

Expedition Team: Our expedition team consisted of 18 Buddhist Monks from the Pema Ts’al Sakya Monastic institute, a team of 4 eye technicians plus an Ophthalmologist/Surgeon from the Himalaya Eye Hospital, and a 7 person team from Dooley-‐Intermed International including; a medical doctor, registered nurse, eye technician, 2 medical assistants, data manager, and documentary photographer/filmmaker. The expedition team conducted 13 clinics during 10 days of General Medical and Eye Screening Camps in multiple villages. All patients were accepted and treatments, including medicines, eyeglasses and surgeries were provided without charge. Medical care was rendered on-‐site. All cataract surgeries were performed in the village of Tsarang over a 2-‐day period. A considerable effort was made to obtain and record epidemiological medical and eye data on the patients. Epidemiological Data Capture: A one-‐page paper form was completed for each patient, recording both general medical and eye related data, including distance visual acuity, chief complaint, pathology, diagnosis, etc. The ophthalmic portion of the data form was designed in cooperation with Dr. Ronald C. Gentile, Professor of Ophthalmology, and Director of Eye Trauma (posterior segment) at the New York Eye & Ear Infirmary. These forms were subsequently entered into an excel spreadsheet using a custom-‐built data entry program on a net-‐book computer. Approximately 600 patient records were entered during the project, with approximately 1,000 patient records entered post-‐project. The original paper records have been retained and are available for examination or verification of data. General Medical Data: Basic medical data were recorded for virtually all patients including; Age, Sex, Village, Height, Weight, Systolic and Diastolic Blood pressure (BP were recorded only for patients 40+ years of age). This portion of the data form was designed in cooperation with Richard Neugebauer, Ph.D., Epidemiologist, Columbia University. This data may be useful for establishing baseline information in regard to growth, height, weight, blood pressure, and prevalence of TB. A considerable amount of hypertension was noted. In at least one village area it is hypothesized that this may be related in some fashion to the mineral content of the municipal water supply (piped from a local river source). Tuberculosis, or suspected tuberculosis, was noted in a number of cases. This TB epidemiological data may have useful community health implications. General medical analysis was restricted to the categories of Age, Sex, Village, Height, Weight, Blood Pressure, and suspected TB. Due to patient load and limited assistance, it was not possible to accurately gather general medical data beyond these categories.

Eye & Vision Data: Distance visual acuity was assessed using “tumbling E” charts at a measured distance of 6 meters on all capable patients and recorded in 6/6 format on the data sheets. Visual acuity was transcribed to 20/20 notation for data entry purposes. Visual acuity was primarily recorded by chart visual acuity. Children too young for chart evaluation were evaluated for ability to “fix & follow”. Those patients unable to see symbols on the chart were evaluated by their ability to CF= count fingers, HM= hand motion, LP= Light perception, NLP= No light perception / blind. Eye patients were requested to state one or more “chief complaints” and were categorized accordingly. Many patients had no complaint and requested an eye “checkup”. Each eye patient was examined and evaluated by a trained eye technician or eye doctor and an any refractive error or pathology was further categorized by the area of the eye involved. Diagnosis and treatment were also recorded. In some villages located along the Kali Gandaki River valley, a large number of scleral abnormalities (primarily pterygium and pinguicula) were noted and recorded in the C/S, conjuctiva / sclera category. This may be related to the high winds and dusty conditions in these villages. Patient cataract information was recorded, and a number of SICS (small incision cataract surgeries) with implantation of rigid IOL (intraocular lens) were performed by Dr. Indra Man Marhajan, Ophthalmologist during 2 days of eye surgeries in the Village of Tsarang. In addition, minor surgeries including removal of foreign bodies, epilation, entropion, and ectropion were performed. Post cataract surgery visual acuity was assessed on the morning following surgery and recorded in the ophthalmic database. Eye & Medical Clinics, Locations & Altitudes: Kagbeni 9,220’ 2,810m Tsuksang 9,780’ 2,980m Samar 12,000 ‘ 3,660m Geling 11,700’ 3,570m Gamig 11,550’ 3,520m Lo Manthang 12,140’ 3,809m (3 clinic days) Tsarang 11,745’ 3,560m (3 clinic days, including 2 surgery days) Notes: Kagbeni & Tsuksang (Chusang) are located along the Kali Gandaki River gorge. In general, this implies somewhat less daylight sun exposure due to the canyon walls. However, this region tends to be very windy with afternoon gusts often reaching 40kph and copious amounts of wind blown dust.

Samar is located on a forested hillside, well above the Kali Gandaki valley, but still on the Southern side of the major passes, thus providing it with more rainfall than villages located on the Tibetan Plateau lying North of the major passes. Geling, Gamig, Lo Manthang, Tsarang and surrounding villages are all located on the Tibetan Plateau, at an average altitude above 3,500m, with a high desert type of environment and minimal geographic protection from the sun. Additionally, since the populations from which the cases are drawn are differentiated to some degree with regard to altitude, percent of daytime working in the shadow of surrounding cliffs, etc. further analysis may reveal additional environmental and geological factors that contribute to risk for cataracts and other ophthalmic diseases. Partner Organizations: Our expedition team collaborated with following partners for this project. All partners had worked together previously and the existing relationships are very good. This expedition was also approved by the King of Mustang, Kinga Jigme Palbar Bista. Dooley-‐Intermed International, NYC, USA based not-‐for-‐profit, provided substantial funding. Pema Ts’al Sakya Monastic Institute, Pokhara, Nepal; providing 18 monks and monastic student volunteers as tri-‐lingual interpreters and eye camp assistants. Mission Himalaya, Kathmandu, Nepal; Nepal registered not-‐for-‐profit, facilitated logistics and in-‐country arrangements. Himalaya Eye Hospital, Pokhara, Nepal; providing eye screening & surgical teams, medical & ophthalmological supplies, surgical equipment, eyeglasses.

Timing This expedition took place in August of 2011, and was specifically planned for the time period just prior to the Nepal harvest season in order to assure maximum participation by villagers. Documentation In addition to the epidemiological research and humanitarian care rendered, we arranged for a filmmaker, Daniel Byers, to make a mini-‐documentary about the project. The result is a film named “Visions of Mustang”. A short film trailer can be viewed on YouTube at http://www.youtube.com/watch?v=wIdMzEc2j38

Expedition Team Our expedition team was comprised of a highly skilled eye surgeon, ophthalmic technicians, a medical doctor, nurse, clinic volunteers, and a group of 18 monastic students, many of whom were from the Mustang region who volunteered to serve as tri-‐lingual translators and assistants throughout the project. The total team was comprised of 18 monk assistants, 33 ponies and horses plus handlers (to transport gear), 5 camp staff & assistants, 5 Explorers Club team members, 3 Nepali team members, and 4 eye technicians plus a highly skilled ophthalmic surgeon from the Himalaya Eye Hospital. Expedition Team Members Dooley Intermed / The Explorers Club Scott Hamilton, CCOA, Expedition Leader Indira Kairam, MD, Expedition Medical Director Basanta Raj Gautam, Expedition Sirdar Melissa Ryan Hamilton Bryson Albrecht (student) Daniel Byers Lisa Chand, RN (Nepal) Trishna Thakur (medical student, Nepal) Himalaya Eye Hospital, Pokhara Nepal Indra Man Maharjan, MD, Medical Director & Chief Ophthalmologist Govinda Nath Yogi, Senior Ophthalmic Assistant Yuva Raj Bohara, Ophthalmic Assistant Pushpa Raj, Ophthalmic Assistant Opendra Chand, Ophthalmic Assistant Pema Ts’al Sakya Monastic Institute Lama Kunga Dhondup, Director Lama Tashi Wangyal, Warden Dhakpa Gyatso Leckshey Choedhar Leckshey Tenpa Leckshey Phuntsok Ngawang Tsultrim Ngawang Rinchen Ngawang Rigzen Ngawang Tashi Ngawang Tsondue Ngawang Phuntsok Ngawang Dhakpa Peter Foti (Hungary) Karma Samten

Expedition Medical Advisors: Robert Ritch, M.D. Distinguished Chair of Ophthalmology Surgeon Director & Chief of Glaucoma Services New York Eye & Ear Infirmary Professor of Ophthalmology New York Medical College Ronald C. Gentile, MD, FACS, FASRS Professor of Ophthalmology New York Medical College Chief, Ocular Trauma Service (Posterior Segment) New York Eye & Ear Infirmary Ram Kairam, M.D. Chairman, Dept. of Pediatrics Bronx Lebanon Hospital New York, N.Y. Verne Chaney, MD, MPH President & Founder Dooley Intermed International New York, N.Y. Maria E. Compte, M.D., M.P.H. & T.M., C-‐TropMed Assistant Professor & Pre-‐Clinical Coordinator School of Health Professions Long Island University Richard Neugebauer, Ph.D Assoc. Professor of Clinical Epidemology Mailman School of Public Health Columbia University Expedition Support Team Members: Narayan Baral, Chief Administrator, Himalaya Eye Hospital Bibhuti Chand Thakur, Mission Himalaya, Kathmandu, Nepal Lobsang Tsering, Exec. Secretary, Pema Ts’al Sakya Monastic Inst. Lama Ghen Rigzen, Pema Ts’al Sakya Monastic Institute Lama Pema Wangdak, Palden Sakya Center, New York Sivani Priya Nattama, Expedition Information Technology

“FORBIDDEN KINGDOM” EXPEDITION MUSTANG, NEPAL, 2011

DESCRIPTIVE EPIDEMIOLOGY ANALYSIS Prepared by Maria E. Compte, MD, MPH &TM April 24, 2012 Total # of Patients: 1,557 Sex: Male: 787

Female: 767 N/A: 3

Age groups: 50+: 655 30-‐49: 402 18-‐29: 236 5-‐17: 240 0-‐ 5: 24 Age range: 3 months -‐ 90 years Approximate median age: 63.7 years Table 1. Patients by Village of Residence : Rank Name of Village # of Patients % 1 Lo Manthang 357 22.93 2 Tsarang 220 14.13 3 Ghami 117 7.51 4 Dhakmar 94 6.03 5 Tsuksang 74 4.75 6 Kagbeni 72 4.62 7 Marang 58 3.72 8 Gelling 57 3.66 9 Tsoshar/Choesar 46 2.95 10 Kemaling 38 2.44 11 Nyamdok 35 2.25 12 Nyamgal 29 1.86 12 Chung Chung 29 1.86 13 Samar 25 1.60 Other 331 21.28 Total 1,557 100

Table 2. Patients by Occupation: Rank Occupation # of Patients 1 Subsistence farmers 986 2 Students 251 3 Clergy (monks, nuns, lamas) 89 4 Teachers 53 5 Service jobs/professions+ 52 6 Homemakers 51 7 Construction* 45 8 Shepherds & Nomads 11 9 Merchants/Traders 9 10 Infants and preschool age children 10 Total 1557 +Excludes teachers *Includes masons, carpenters, painters, repairmen Table 3. Prevalence of Medical Complaints/Diagnoses (non-‐ophthalmologic)*: Rank Clinical Diagnosis # Cases Prevalence** 1 Arterial Hypertension+ 286 183.7 2 Musculoskeletal++ 146 93.8 3 ENT+++ 107 68.7 4 TB*** 93 59.7 5 GI^ 82 52.7 6 Dental & periodontal 29 18.6 7 Hepatic and biliary^^ 24 15.4 8 Dermatitis & sup.

mycoses 18 11.5

9 Acute alcoholic syndrome 8 5.1 *Many patients presented with more than one complaint **Crude Prevalence Rates per 1,000 pop. +Most cases involved both systolic and diastolic hypertension ++Most prevalent were arthritic conditions and low back pain +++ Most prevalent were sinusitis and hearing loss ***Includes current confirmed or suspected TB and Hx of TB ^ Most prevalent were gastritis, diarrheal disease, giardiasis and other parasitoses ^^ Jaundice and hepatitis

Table 4. Prevalence of Ophthalmologic Complaints/Diagnoses*: Rank Ophthalmologic

Diagnosis # Cases Prevalence**

1 Refractive errors+ 302 194.0 2 Conjunctivitis++ 296 190.1 3 Cataracts+++ 233 149.6 4 Pterigium 136 87.3 5 Pinguecula 93 59.7 6 Aphakia & Pseudophakia 63 40.4 7 Eye gland disease*** 39 25.0 8 Corneal disease^ 29 18.6 9 Xerophthalmia^^ 26 16.7 10 Retina & Choroid

disease^^^ 16 10.3

11 Eyelid conditions< 14 9.0 12 EOM & CN conditions<< 12 7.7 13 Glaucoma 9 5.7 14 Entropion & trichiasis<<< 6 3.8 15 Eye trauma 5 3.2 16 Chalazion 3 1.9 * Many patients were diagnosed with more than one ophthalmologic condition **Crude Prevalence Rates per 1,000 pop. + Most prevalent was presbyopia; most pts. received corrective eyeglasses on site + +Includes acute and chronic; irritative, allergic, viral, & bacterial, and possibly some early or moderate trachoma +++ Includes early, immature, mature, and hypermature; most of subcapsular location *** Most prevalent were dacrocystitis and meibomianitis ^ Includes clouding, keratitis, scarring, possible trachoma, and ulceration ^^ Dry eye syndrome ^^^ Most prevalent was age-‐related macular degeneration <Includes belpharitis, ptosis, etc., except entropion << Includes strabismus and nystagmus <<< Likely trachomatous sequelae Surgical Clinic Epidemiology: Ophthalmologic Surgery Clinic (village of Tsarang): Cataract surgeries (SICS-‐IOL ): 79 patients : 82 eyes Entropion lid surgeries: 6 patients: 8 eyes Trichiasis epilation procedure: 2 patients: 2 eyes Cornea foreign body removal: 2 patients: 3 eyes Pterigion excision: 1 patient: 1 eye Lid cyst excision: 1 patient: 1 eye Total # of patients: 89 Total surgical procedures: 97 Crude Incidence rate for Surgical Procedures: 6.22 per 100 pop.

Note: a few patients received surgical procedures in both eyes, or more than one type of surgical procedure done in one or both eyes Table 5. Ophthalmologic Surgical Procedures by Residence, Sex, Age, Eye Affected and Type of Procedure: # Village of residence Sex Age Eye Surgical Procedure 1 Kagbeni M 65 OD SICS 2 Kagbeni F 79 OS SICS 3 Tsuksang F 73 OD Corneal FB extraction 4 Gyakar M 78 OD SICS 5 Gelling F 73 OD SICS 6 Gelling F 78 OD SICS 7 Ghami M 81 OD SICS

Trichiasis epilation 8 Ghami M 78 OS SICS 9 Ghami M 66 OS SICS 10 Ghami M 55 OD SICS 11 Ghami F 73 OS SICS 12 Dhakmar M 55 OS SICS 13 Ghami M 67 OD SICS 14 Dhakmar F 71 OD SICS 15 Dhakmar F 44 OS SICS 16 Ghami M 69 OD SICS 17 Dhakmar F 26 OS Lid cyst excision 18 Ghami F 66 OS SICS 19 Kemaling F 64 OD SICS 20 Kemaling F 64 OD SICS 21 Thinkar M 74 OS SICS 22 Kemaling F 69 OD SICS 23 Tsoshar M 70 OS SICS 24 Chung Chung M 78 OD SICS 25 Chung Chung F 78 OD SICS 26 Choesar F 60 OD SICS 27 Nyenol F 75 OD SICS 28 Thinkar F 71 OD SICS 29 Choesar F 60 n/a SICS 30 Phurphak M 72 OS SICS 31 Tsosung M 72 OD SICS 32 Namdok M 67 OU SICS 33 Lo Manthang F 75 OD SICS 34 Lo Manthang M 65 OD SICS 35 Lo Manthang M 79 OD SICS 36 Lo Manthang M 74 OD SICS 37 Lo Manthang M 77 OD SICS 38 Lo Manthang M 77 OD SICS 39 Lo Manthang M 31 OS SICS 40 Lo Manthang F 77 OS SICS 41 Phurpak F 55 OD SICS 42 Phuwa F 55 OS SICS

#

Village of residence

Sex

Age

Eye

Surgical Procedure

43 Lo Manthang M 71 OD SICS 44 Lo Manthang F 55 OD Entropion lid surgery 45 Lo Manthang F 75 OS SICS 46 Lo Manthang F 90 OD SICS 47 Lo Manthang F 76 OD SICS 48 Nyinol M 78 OU SICS 49 Nyinol M 70 OS SICS 50 Nyamdok F 68 OD SICS 51 Lo Manthang F 82 OD SICS 52 Lo Manthang F 75 OS SICS 53 Lo Manthang F 50 OD SICS 54 Lo Manthang M 32 OU Corneal FB removal 55 Lo Manthang M 78 OD SICS 56 Dhakmar F 73 OS Entropion lid surgery 57 Dhe M 70 OS SICS 58 Tsarang M 55 OS SICS 59 Marang F 74 OD Entropion lid surgery 60 Marang F 50 OD SICS 61 Tsarang M 70 OD SICS 62 Dhakmar F 65 OS Trichiasis epilation 63 Tsarang M 78 OS SICS 64 Tsoshar M 71 OD SICS 65 Marang M 78 OD SICS 66 Yara F 46 OS SICS 67 Tsoshar F 80 OD SICS 68 Samar F 77 OD SICS 69 Dhe M 74 OD SICS 70 Tsarang F 75 OD SICS 71 Tsarang F 75 OD SICS 72 Marang F 48 OS SICS 73 Lo Manthang M 67 OS SICS 74 Lo Manthang F 63 OU

OU SICS Entropion lid surgery

75 Tsarang F 60 OS SICS 76 Tsarang F 74 OD SICS 77 Dhakmar M 61 OS SICS 78 Thinkar M 55 OS SICS 79 Marang F 60 OD SICS 80 Tsoshar M 67 OS SICS 81 Nyamdok M 70 OS SICS 82 Nyamdok F 78 OD SICS 83 Lo Manthang M 73 OD SICS 84 Lo Manthang F 75 OS SICS 85 Samar M 75 OS SICS 86 Gyakar M 50 OS SICS

87 Marang F 49 OU Entropion lid surgery 88 Gyakar F 75 OS Entropion lid surgery 89 Lo Manthang F 45 n/a Pterigion removal Cataract Clinic Epidemiology: Total # of Patients with Dx of Cataract: 233 Total # of Eyes with cataracts: 346 Number of Patients with Dx of Bilateral Cataract Disease: 113 (48%) Patients with Cataracts by Sex: Male: 121 Female: 108 N/A: 3 Sex ratio: 1.12 M:F Patients with Cataracts By Age: 55 y.o. and older: 211. Crude Prevalence Rate= 135.5 per 1,000 pop. < 55 y.o.: 20. Crude Prevalence Rate= 12.8 per 1,000 pop. Patients with Cataracts by Sex and Age: Males: 55 y.o. and older: 110 < 55 y.o.: 10 Age N/A: 1 Average age of Male Cataract Patients: 64.9 y.o. Females: 55 y.o. and older: 98 < 55 y.o.: 9 Age N/A: 1 Average age of Female Cataract Patients: 60.6 y.o. General Crude Prevalence Rate for Cataracts in the total Patient Population= 149.6 per 1,000 pop. Cataract Surgery (SICS-‐IOL) Procedures in Eye Outreach Clinic (Tsarang): # of SICS-‐IOLs in Male Patients: 40 SICS-‐IOL Rate in Males: 215.0 per 1,000 pop. # SICS-‐IOLs in Female Patients: 39 SICS-‐IOL Rate in Females: 251.6 per 1,000 pop. Rate Ratio for SICS-‐IOL=: 1.15 F:M Crude Incidence Rate for SICS-‐IOL in Tsarang Eye Clinic: 35 procedures per 100 patients with cataracts Overall Cataract Surgery Coverage Rate for Tsarang Eye Clinic: 237 per 1,000 pop.

Descriptive Analysis of Main Eye Conditions by Altitude: Altitude # Conjunctival &

Scleral Conditions*

Rate

# Cataracts**

Rate

Lower (below 10,000ft.)^

107

. 572

21

.112

Higher (above 10,000ft.)^^

444

.324

212

.155

Totals 551 .354 233 .149 ^ Includes villages of Kagbeni, Tsuksang, and other smaller settlements ^^ Includes villages of Samar, Geling, Gaming, Lo Manthang, Tsarang, and other smaller settlements *Conjunctival conditions include mostly diagnoses of conjunctivitis & xerophthalmia; sclera conditions include mostly diagnoses of pterigion & pinguecula **Cataract diagnoses include early, immature, mature, and hypermature Overall Rate Ratio, Conjunctivo-‐scleral Conditions (CSC) vs. Cataracts (Ct): 2.37 Rate Ratio CSC/Ct for Lower vs. Higher Altitude: 1.76 Rate Ratio Ct/CSC for Higher vs Lower Altitudes: 1.38 Risk Association Measurements for CSC based on altitude level (lower vs. higher altitudes): Odds Ratio: 2.79 (CI= 2.09 to 3.80; z= 6.645; p<.0001) Interpretation: It appears to be a statistically significant association for a moderately increased risk of development of-‐-‐ mostly chronic-‐-‐ conjunctivo-‐scleral conditions in this Mustangi population for those people residing at lower altitudes (below 10,000 ft., e.g. the semi-‐desertic high plateaus of the Kali Gandaki river canyon) as compared with villagers residing at higher altitudes (above 10,000 ft). Risk Association Measurements for Ct based on altitude level (higher altitudes vs. lower altitudes): Odds Ratio: 1.45 (CI=.8982 to 2.3317; z=1.516; p=.1288) Interpretation: There appears to be no statistically significant risk association in this population between the development of cataract disease in those residing at higher altitudes (above 10,000 ft.), as compared to those Mustangi residents living at lower altitudes (below 10,000 ft.).

Discussion of Research & Epidemiology Analysis These results indicate that a substantial amount of basic physiological and ophthalmological data can be effectively collected in a field environment with a minimal logistical requirement in terms of equipment. Research interviews and patient medical history required dedicated multi-‐lingual personnel, and the inclusion of local monastic personnel was a great benefit in this regard. The use of these data collection methods was indicative of the efficacy of “piggy-‐backing” extensive epidemiological data collection on remote humanitarian medical projects in a remote high mountainous field environment. These findings have some important limitations, since we are dealing with a patient population who is generally overall older and, even in the case of the "lower altitude residents", still live at fairly high elevations, where they are exposed to other environmental factors beyond UV radiation, which might increase the overall risk of cataracts. Genetics, as well as chronic conditions common in the geriatric population, may also play a role. A comparative risk association study between the prevalence of main ophthalmic conditions in residents of lower and higher altitude shows that there is a statistically significant probability of a moderate association between residence in the Kali Gandaki gorge and an increased prevalence of conjunctivo-‐scleral conditions. It is hypothesized that this may be due to the high winds and dusty conditions in this area. While there was a slightly higher rate, we did not find a statistically significant risk association for cataracts in Mustangi residents of higher altitudes (12,000-‐13,000ft.) as compared to those living in slightly lower altitudes (9,000-‐10,000 ft.).

Mustang cataract patient with daughters, Tsarang Village

photo credits: Daniel Byers

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Forbidden)Kingdom)Drishti)Expedition) Flag#93)Report) · Forbidden)Kingdom)Drishti)Expedition) Flag#93)Report) Kingdom)of)Mustang ... Cataract)in)Tibet)eye)study.)volume)107];)and)a)