Ozone Exposure, Outdoor Physical Activity, and Incident Type 2 Diabetes in the SALSA Cohort of Older Mexican Americans

Abstract

BACKGROUND: Type 2 diabetes is a leading contributor to the global burden of morbidity and mortality. Ozone (O 3 ) exposure has previously been linked to diabetes. OBJECTIVE: We studied the impact of O 3 exposure on incident diabetes risk in elderly Mexican Americans and investigated whether outdoor physical activity modifies the association. METHODS: We selected 1,090 Mexican American participants from the Sacramento Area Latino Study on Aging conducted from 1998 to 2007. Ambient O 3 exposure levels were modeled with a land-use regression built with saturation monitoring data collected at 49 sites across the Sacramento metropolitan area. Using Cox proportional hazard models, we estimated the risk of developing incident diabetes based on average O 3 exposure modeled for 5-y prior to incident diabetes diagnosis or last follow-up. Further, we estimated outdoor leisure-time physical activity at baseline and investigated whether higher vs. lower levels modified the association between O 3 exposure and diabetes. RESULTS: In total, 186 incident diabetes cases were identified during 10-y follow-up. Higher levels of physical activity were negatively associated with incident diabetes [hazard ratio ðHRÞ = 0:64 (95% CI: 0.43, 0.95)]. The estimated HRs for incident diabetes was 1.13 (95% CI: 1.00, 1.28) per 10ppb increment of 5-y average O 3 exposure; also, this association was stronger among those physically active outdoors [HR = 1:52 (95% CI: 1.21, 1.90)], and close to null for those reporting lower levels of outdoor activity [HR = 1:04 (95% CI: 0.90, 1.20), p interaction = 0:01]. CONCLUSIONS: Our findings suggest that ambient O 3 exposure contributes to the development of type 2 diabetes, particularly among those with higher levels of leisure-time outdoor physical activity. Policies and strategies are needed to reduce O 3 exposure to guarantee that the health benefits of physical activity are not diminished by higher levels of O 3 pollution in susceptible populations such as older Hispanics.

Long-term air pollution exposure and markers of cardiometabolic health in the National Longitudinal Study of Adolescent to Adult Health (Add Health) Study

“…We used data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), an ongoing, nationally representative cohort of adolescents in grades 7-12 during the 1994-95 school year. Add Health used a multistage, stratified, school-based, cluster sampling design to select a probability sample of more than 20,000 adolescents from school rosters for in-home interviews at Wave I (WI) in 1994-95 (ages [12][13][14][15][16][17][18][19]. The cohort has been followed up with four subsequent interviews: WII in 1996 (ages [13][14][15][16][17][18][19][20]; WIII in 2001-02 (ages 18-26); WIV in 2008-09 (ages 24-32); and WV in 2016-18 (ages 33-43).…”

“…Add Health used a multistage, stratified, school-based, cluster sampling design to select a probability sample of more than 20,000 adolescents from school rosters for in-home interviews at Wave I (WI) in 1994-95 (ages [12][13][14][15][16][17][18][19]. The cohort has been followed up with four subsequent interviews: WII in 1996 (ages [13][14][15][16][17][18][19][20]; WIII in 2001-02 (ages 18-26); WIV in 2008-09 (ages 24-32); and WV in 2016-18 (ages 33-43). 27,28 Response rates have ranged from 72% to 90% across waves, and non-response bias has been minimal.…”

“…There is also evidence to suggest that long-term exposure to air pollution, including PM2.5 and O3, is associated with accelerated atherosclerosis, 15 elevated blood pressure and increased mean arterial pressure, 16 , obesity, 17,18 and diabetes. 19,20 Much of the work on air pollution and cardiovascular disease risk has focused on middle-aged and older adults, e.g., ≥45 years, the demographic age group at highest risk for morbidity and mortality associated with cardiovascular disease.…”

The effect of ambient ozone exposure on three types of diabetes: a meta-analysis

“…Hathout et al found the positive correlation between ozone and T1D [ 18 ], but a negative correlation was observed by Elten et al [ 11 ]. A study in areas with low average ozone exposure found significant positive effects [ 21 ], but not in areas with higher levels [ 62 ]. Results of studies also varies on the association between GDM and ozone exposure [ 19 , 41 ].…”

Effects of Air Pollution on the Health of Older Adults during Physical Activities: Mapping Review

“…This can lead to the transport of pollutants to the deepest region of the respiratory system, with harmful consequences for health [ 12 ]. In addition, during the natural process of aging, several comorbidities, such as obesity, hypertension, atherosclerosis, diabetes, cardiovascular diseases, and neurodegenerative diseases [ 13 , 14 , 15 , 16 , 17 ], can be aggravated by exposure to atmospheric pollutants.…”