Abstract
Introduction: Residing at moderate altitudes has been associated with various health benefits also affecting mortality risk. This study investigates life expectancy and disease-specific mortality rates among populations in the Italian Alps and in northern Italian lowland regions. Additionally, cardiometabolic health and serum metabolite concentrations of residents in an Alpine province across three distinct elevation zones (<1,000 m, 1,000-1,500 m, and >1,500 m above sea level) are studied.
Methods: Data on life expectancy and mortality rate (per ten thousand) were retrieved from the ISTAT database for 6 provinces located in the Italian Alps and 6 provinces at sea level near the Alps. Using cross-sectional data from a sub-sample of the Cooperative Health Research in South Tyrol (CHRIS) study (n=6,292), we fitted multivariable adjusted logistic regression models to investigate associations between altitude and cardiometabolic health, determined by the Cumulative Illness Rating Scale. Moreover, associations between altitude and 175 serum metabolites were evaluated through linear regression models (n=1,447).
Results: Population size and sex distribution were similar between provinces (p>0.485). Life expectancy at 65 years differed between areas (20.8±0.4 vs 20.1±0.3, for Alps vs sea-level, respectively, p=0.026). Mortality rate for diseases of the circulatory system was lower in the Alps than at sea-level (35.3±5.7 vs. 44.5±6.8, respectively, p=0.026). No statistically significant differences were found for mortality (Alps vs. sea-level) from all causes (108.1±15.7 vs. 126.1±15.5, p=0.065), cerebrovascular diseases (8.4±2.5 vs. 12.6±3.1, p=0.065), endocrine, nutritional and metabolic diseases (3.6±1.0 vs. 5.0±1.0, p=0.065), neoplasms (31.1±4.7 vs. 34.3±2.4 p=0.394) and diseases of the respiratory system (8.3±1.7 vs. 8.8±1.7, p=0.589). In the CHRIS study sample, living at moderate vs. low altitude level was associated with lower odds of mild to severe conditions in the hypertension (OR:0.77; 95%CI: 0.62-0.96) and endocrine-metabolic domain (OR:0.77, 95%CI: 0.61-0.97). No differences in blood serum metabolic profiles were observed between people living at different altitude levels.
Conclusions: Living in the Italian Alps seems to have a positive effect on life expectancy and mortality from certain diseases compared to living at sea level in northern Italy. Furthermore, living at moderate altitude conferred some cardiometabolic health benefits in the CHRIS study population, even after corrections for confounding factors. The metabolite profile in a sub-sample did, however, not reveal any significant differences between altitude levels.