**Background:** Non-communicable diseases (NCDs) are the leading cause of morbidity and mortality globally, with 78% of NCD-related deaths occurring in low- and middle-income countries (LMICs). Indigenous populations in LMICs are severely underrepresented in medical research, as nationally representative surveys often exclude small or rural ethnic groups. Nepal has over 120 ethnolinguistic groups, 59 of which are officially recognized as indigenous. Previous nationally representative surveys in Nepal reported a hypertension prevalence of 26% and overweight/obesity prevalence of 21% in the general population, but data on specific indigenous communities remain scarce. This study aimed to assess the prevalence of three NCD risk factors—obesity, hypertension, and tachycardia—and identify dietary and lifestyle determinants in underrepresented indigenous Nepali populations.
**Methods:** This population-based cross-sectional study was conducted from February to May 2016. A total of 337 individuals from 12 ethnic groups (11 officially recognized as indigenous: Bote, Chepang, Darai, Kusunda, Maajhi, Newar, Raji, Raute, Tamang, Thami, Tharu; and one Dalit group: Musahar) were recruited via household visits. After excluding 26 individuals with incomplete data, 311 participants remained. Inclusion criteria were adults ≥18 years whose parents and grandparents were from the same ethnic group. Only unrelated individuals (no shared grandparent) were selected, with one participant per household. Demographic, anthropometric, environmental, and dietary data were collected using a survey questionnaire aligned with the WHO STEPS Instrument, modified for traditional Nepali lifestyles. Blood pressure and heart rate were measured using an automatic monitor (Omron BP791IT); four readings were taken at 3-minute intervals and the last three were averaged. Hypertension was defined as SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg. Weight and height were measured three times and averaged; BMI was calculated accordingly. Statistical analyses included chi-squared tests, univariate and multivariable logistic regressions, and linear regression, performed using STATA 16.0 and R 3.6.1.
**Key Results:** The mean systolic and diastolic blood pressures were 121.3±19.5 mmHg and 81.3±11.8 mmHg, respectively. Overall hypertension prevalence was 23.8% (27.7% in the Hills, 19.3% in the Terai). Hypertension was more prevalent in men (31.7%) than women (16.8%, P=0.003). Mean SBP was 127.0±19 mmHg in men vs. 115.5±17.9 mmHg in women (P=0.049); mean DBP was 84.0±11.7 mmHg vs. 78.9±11.3 mmHg (P=0.003). Obesity prevalence was 0.64% (n=2) and tachycardia prevalence was 3.22% (n=10). Mean BMI was 21.6±3.2; 15% (n=47) were overweight. In multivariable logistic regression, age was strongly associated with hypertension: individuals aged 40–61 had an adjusted OR of 2.872 (95% CI: 1.324–6.232, P=0.008) and those aged 62–83 had an adjusted OR of 7.668 (95% CI: 2.826–20.805, P<0.001) compared to those aged 18–39. Overweight/obese individuals (BMI ≥ 25) had an adjusted OR of 4.048 (95% CI: 1.234–13.272, P=0.021) compared to underweight individuals. Chewing tobacco use was associated with hypertension (adjusted OR=2.492, 95% CI: 1.102–5.631, P=0.028). Weekly/daily milk consumption was also associated with hypertension (adjusted OR=3.597, 95% CI: 1.333–10.139, P=0.012). The full multivariable model explained approximately 13.9% of the variance in hypertension (adjusted R²=0.139). Among hypertensive individuals, 13.5% had none of the five established risk factors (alcohol consumption, low vegetable diet, physical inactivity, overweight/obesity, smoking). Having one or more risk factors significantly increased the odds of hypertension (OR for 1 risk factor: 2.887, 95% CI: 1.337–6.232, P=0.007; OR for 2 risk factors: 4.743, 95% CI: 2.077–10.831, P<0.001).
**Clinical Implications:** This study reveals that hypertension is prevalent (23.8%) in underrepresented indigenous Nepali populations, comparable to the general Nepali population (26%). However, many classic hypertension determinants—education, alcohol consumption, smoking, physical inactivity—were not individually associated with hypertension in this cohort, likely due to lifestyle differences (e.g., 80.7% were physically active, 97% consumed fresh vegetables twice daily, 67.5% ate home-cooked meals). The finding that 13.5% of hypertensive individuals had none of the five established risk factors, and that the full model explained only ~14% of hypertension variance, strongly suggests that additional, population-specific determinants remain unidentified. These may include cultural dietary elements (e.g., fermented food consumption, salt intake), genetic factors, or environmental exposures not captured by standard survey instruments. The results indicate that intervention strategies developed for the general Nepali population may be insufficient for indigenous communities, and that larger, culturally tailored studies are urgently needed to identify novel risk factors and inform targeted public health approaches.