COPD and Obesity: Is There a Dose-Response Relationship in Nonsmokers?

A potential risk factor for chronic obstructive pulmonary disease (COPD) is obesity, but factors linking obesity to COPD in never-smokers have not received much attention, according to an analysis of data obtained from the US Centers for Disease Control and Prevention’s (CDC’s) Behavioral Risk Factor Surveillance System (BRFSS). Findings from the study were published in the Journal of Obesity.

Investigators sought to explore the association between COPD and obesity levels in a nationally representative sample of non-Hispanic white never-smokers using data derived from the CDC’s BRFSS. Pearson’s chi-square tests and logistic regression analyses were conducted in a large sample of respondents age ≥50 (76,004 women and 37,618 men) who reported never smoking.

A dose-response relationship was observed in both women and men, with the prevalence of COPD increasing significantly from 3.5% in women of a healthy weight (body mass index [BMI] <25 kg/m²) to 13.4% in women with class III obesity (BMI ≥40 kg/m²; P <.001). In men, the prevalence of COPD was similar in individuals in the normal weight and overweight categories (2.5% and 2.2%, respectively), but was considerably higher in individuals with class I and class II obesity (3.8%), as well as individuals with class III obesity (7.6%; P <.001).

After adjusting for  potential confounders (age, gender, height, education, household income, household conditions [marital status and number of individuals residing in household], and type of health plan), the odds of developing COPD were 71% higher in men with class I or II obesity (odds ratio [OR], 1.71; 95% CI, 1.43-2.04) and 3-fold higher in men with class III obesity (OR, 3.21; 95% CI, 2.46-4.20) compared with men of normal weight. Moreover, in women with class III obesity, the likelihood of developing COPD was 4.00 times higher compared with women of healthy weight (95% CI, 3.52-4.55).

The investigators concluded that regular COPD screening is warranted in never-smoking obese patients age ≥50. Additional research is needed in order to examine possible mechanisms for this association, including the relationship between chronic inflammation and obesity and the effect of central obesity on respiratory system mechanics.

Reference

Fuller-Thomson E, Howden KEN, Fuller-Thomson LR, Agbeyaka S. A strong graded relationship between level of obesity and COPD: findings from a national population-based study of lifelong smokers [published online November 20, 2018]. J Obes. doi: 10.1155/2018/6149263