1. Yueh-Han Hsu 1,2, MD, MPH, PhD; Wen-Chen Tsai 2, DrPH; Wei Chen 1, MD 1 Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chia-Yi City, Taiwan 2 Department of Health Services Administration, China Medical University, Taichung City, Taiwan Abstract Introduction The health of physicians may influence the quality of the national health care; only physicians with sound health may deliver high quality health services. With profound medical knowledge and healthcare network, doctors were expected to have lower risk of cancer. However, doctors have heavy work-loads since their student ear, they might not necessarily conduct healthy life pattern. Previous research were inconsistent with regards to area and study design. Purpose and Methods We investigated the risk of 15 major cancers of the doctors in Taiwan from a nation-wide health claims database 2000~2012 and Taiwan Cancer Registry File. We included all doctors aged over 25 who practiced medicine in 2000. The control group included all non-health care people with same age limit in 2000. The exclusion criteria were previous history of cancers, AIDS and organ transplant. We conducted propensity score matches of 1:1 ratio with gender, age, residence urbanization and severity of comorbidity by Charles Comorbidity Index (CCI). We used Cox proportional hazard to evaluate the risks of cancers among these groups.Results In all, the case numbers in both groups were 29713. Till the end of follow-ups, there were 1326 and 1533 incident cases of cancers in the doctors and non-doctors groups. The distribution of cancers in both groups were different. In the doctor group, the most prevalent 5 cansers were breast cancer, colorectal cancer, prostate cancer, hepatoma and lung cancer; for non-doctor group, they were breast cancer, hepatoma, colorectoal cancer, lung caner and orapharyngeal cancer. The cancer distributions in both genders of doctors were also different. Under Cox model, doctors had 10% lower overall cancer risk (4.46% vs 5.16%, p<0.001). Among doctors, male had lower cancer risk (adjusted HR (aHR) 0.63, 95% confidence interval (CI) 0.51-0.78, p <0.001). Comparing the cancer risks in 15 major cancers between doctors and non-doctors, doctors had higher risks of prostate cancer (aHR 1.26, 95%CI 1-1.59, p=0.046) and thyroid cancer (aHR 3.16, 95%CI 1.69-5.90, p<0.001). Table. 1 Characteristics of participants after 1:1 propensity score matching Higher risk of prostate cancer and thyroid cancer in doctors in Taiwan Conclusions Doctors have higher risk of prostate cancer and thyroid cancer in Taiwan Variable After matching (1:1) TotalNon-doctorsDoctors P value N%N%N% Total59426100.002971350.002971350.00 Sex1.000 Female640610.78320310.78320310.78 Male5302089.222651089.222651089.22 Age1.000 ≦ 34 1554426.16777226.16777226.16 35-442022034.031011034.031011034.03 45-541163019.57581519.57581519.57 55-6442667.1821337.1821337.18 65-7441707.0220857.0220857.02 ≧ 75 35966.0517986.0517986.05 Average age (Mean, Std)45.2014.5145.1414.6345.2514.39 Level of residence urbanization1.000 Level 1 (ref)2387240.171193640.171193640.17 Level 2 and 32715645.71357845.71357845.7 Level 4 and 5637410.73318710.73318710.73 Level 6 and 720243.4110123.4110123.41 CCI score1.000 02053034.551026534.551026534.55 1~32198436.991099236.991099236.99 4~61098818.49549418.49549418.49 7~941827.0420917.0420917.04 ≧ 10 17422.938712.938712.93 VariableUnadjusted HRP value Adjusted HR 95% CIP value Sex Female (ref) Male 1.330.0050.630.510.78<0.001 CCI score 0 (ref) 1~38.31<0.0018.084.4214.77<0.001 4~619.76<0.00114.798.1126.96<0.001 7~942.68<0.00123.4512.8442.82<0.001 ≧ 10 63.41<0.00126.6714.5648.86<0.001 Cancers of primary anatomic sites Non-doctorsDoctorsAdjusted HR d NoIncidence a No Incidence a HR95%CIP value Breast cancer c 3085.4747134.20 1.581.002.490.052 Colon, rectum, rectosigmoid junction and anus cancer22769.6723572.10 1.030.861.240.742 Prostate gland cancer b 13044.6516556.71 1.261.001.590.046 Liver and intrahepatic bile ducts cancer23271.2115848.44 0.680.560.83<0.001 Trachea, bronchus and lung cancer20964.1214644.75 0.690.560.86<0.001 Ovary, fallopian tube and broad ligament cancer c 00.001131.24 -- Stomach cancer7623.278124.80 1.060.781.450.716 Corpus uteri cancer c 25.68617.04 3.000.6114.850.179 Bladder cancer6720.514313.16 0.640.440.940.022 Thyroid gland cancer133.984112.54 3.161.695.90<0.001 Nasopharynx cancer4513.77298.87 0.650.411.030.066 Cervix uteri cancer c 38.513 1.000.204.940.997 Oral cavity, oropharynx and hypopharynx cancer14745.05257.650.170.110.26<0.001 Esophagus cancer6118.67164.89 0.260.150.45<0.001 Skin cancer206.12133.98 0.650.321.310.226 Other cancer28386.9231797.43 1.120.951.310.170 a Incidence: per 100,000 person-years. b Incidence of per 100,000 person-years for men. c Incidence of per 100,000 person-years for women. d adjusted for age, sex Also adjusted for age and level of residence of urbanization Table. 1 Characteristics of participants after 1:1 propensity score matching Table. 2 Risk factors of cancer in doctors under Cox proportional model Table. 3 The adjusted risk of cancers in doctors and non-doctors under Cox proportional model P1.05