Association between very high altitude and frailty syndrome in rural community residents of Junin Department, Peru

Introduction: Frailty syndrome represents a state of vulnerability that significantly affects the elderly. Chronic exposure to high altitudes may accelerate this process due to chronic hypoxia. Peru's aging population has increased from 5.7% in 1950 to 13.6% in 2023, with 42.6% residing in rural areas. This demographic shift has led to increased prevalence of geriatric syndromes, particularly frailty syndrome. The prevalence of frailty syndrome varies globally, ranging from 5.8% to 27% in European countries and 19.6% in Latin America and the Caribbean. In Peru, previous studies report prevalences between 7.7% and 27.8%, with high-altitude Andean communities showing higher rates. The study's purpose was to determine the association between very high altitude and frailty syndrome in rural community residents of Junín Department, Peru. Methods: A cross-sectional study was conducted in 2023. A total of 393 participants aged ≥60 years residing in rural communities located at high altitudes (2500–3500 m above sea level (a.s.l.)) and very high altitudes (3500–5800 m a.s.l.) were evaluated. Frailty syndrome was assessed according to Fried's criteria: unintentional weight loss (≥4.5 kg in the past year), self-reported exhaustion, low physical activity measured by the Minnesota Leisure Time Activity Questionnaire (lowest quintile <383 kcal/week in men, <270 kcal/week in women), slow walking speed (adjusted for sex and height), and muscle weakness (grip strength below 20% of normal limit, adjusted for BMI and sex). Categories were defined as robust (0 criteria), prefrail (1–2 criteria), and frail (≥3 criteria). Non-probabilistic convenience sampling was used to select 14 population centers. Bivariate analysis and Poisson regression were performed to determine associations. Results: The overall prevalence of frailty syndrome was 44.53% (n=175). Among the frail elderly, 80.6% (n=141) resided in very-high-altitude communities. A significant association was found between very high altitude and frailty (adjusted prevalence ratio=3.11, 95%CI 1.87–5.17, p<0.001). Associated factors included female sex (63.43% of frail versus 47.25% of non-frail, p=0.001), primary education or no formal education (94.28%), agricultural occupation (62.86% of frail versus 39.91% of non-frail, p=0.001), regular self-perceived health (58.86% of frail versus 47.25% of non-frail, p=0.001), and mild functional dependence (54.29%). Cognitive impairment was present in 73.14% of frail versus 15.60% of non-frail elderly (p=0.001). Moderate/severe physical limitation affected 58.86% of frail versus 20.64% of non-frail elderly (p=0.001). Conclusion: There is a significant association between residing at very high altitudes and frailty syndrome in the elderly from Peruvian rural communities. Elderly residents at very high altitude have three times higher prevalence of frailty than residents at high altitudes. The findings suggest the need to implement specific preventive programs for this vulnerable population. Chronic exposure to hypobaric hypoxia at extreme altitudes may accelerate the depletion of physiological reserves, predisposing to frailty development. Future longitudinal studies are needed to establish causal relationships and clinical trials are needed to evaluate specific interventions for high-altitude populations.