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Obesity contributes to early-onset heart problems and longer hospital stays

Nearly 65 percent of the U.S. population is overweight (body mass index or BMI of 25 kg/m2 or more), and 30.5 percent of the population is obese (BMI of 30 kg/m2 or more). Obesity increases the risk of developing cardiovascular and other diseases. Although obese individuals undergo coronary angioplasty and other techniques to relieve coronary narrowing at a younger age than people who are not obese, weight does not appear to affect their recovery from these procedures, according to a study supported in part by the Agency for Healthcare Research and Quality (HS11282). On the other hand, obese individuals stay in the hospital longer for cardiac and other problems than normal-weight individuals, according to another AHRQ-supported study (National Research Service Award T32 HS00032). Both studies are discussed here.

Poston, W.S., Haddock, C.K., Conard, M., and Spertus, J.A. (2004). "Impact of obesity on disease-specific health status after percutaneous coronary intervention in coronary disease patients." International Journal of Obesity 28, pp. 1011-1017.

Obesity is known to elevate the risk of postoperative complications following coronary artery bypass graft surgery (CABG). However, obesity doesn't seem to affect recovery from percutaneous coronary intervention (PCI), which includes coronary angioplasty and other non-CABG revascularization procedures, according to this study. The researchers classified 1,631 PCI patients as underweight (BMI less than 20), normal weight (BMI 20 to 25), overweight (BMI 25 to 30), or obese (class 1 obese, BMI 30 or more; class II and III obese, BMI 35 or more). They examined by weight class patients' need 12 months later for repeat procedure, survival, quality of life, and health status using angina-specific and general health questionnaires.

Obese patients with and without a history of revascularization were significantly younger than overweight, normal weight, or underweight patients at the time of PCI. However, obese patients had similar survival, quality of life, and disease-specific health status as normal-weight patients 1 year after PCI. Also, there was no association between obesity status and need for repeat revascularization or 12-month mortality.

Overweight and obese patients appeared to benefit just as much from PCI as normal-weight patients. In contrast, underweight patients reported lower quality of life and poorer physical functioning than the other BMI groups 1 year after PCI. These results suggest that clinicians should not significantly alter their recommendations for PCI based on patients' overweight or obesity status.

Zizza, C., Herring, A.H., Stevens, J., and Popkin, B.M. (2004). "Length of hospital stays among obese individuals." American Journal of Public Health 94, pp. 1587-1591.

Obese individuals stay in the hospital longer than normal-weight individuals, according to this study. As BMI increased, so did the number of inpatient hospital days. In all likelihood, treatment and prevention of obesity will reduce use of hospital care and the subsequent health care costs associated with the obesity epidemic, suggest the researchers. They used data from the first National Health and Nutrition Examination Survey Epidemiologic Followup Survey to estimate hospital stay differences over four 5-year periods among individuals in the following BMI groups: less than 18.5, underweight; 18.5 to 24.9, normal weight; 25 to 29.9, overweight; 30 to 34.9, obese; and 35 or above, severely obese.

Overweight and obese individuals had longer hospital stays than normal-weight individuals, although the association between BMI and length of stay varied over the four time periods. For example, overweight, obese, and severely obese individuals had 25 percent, 45 percent, and 54 percent, respectively, longer hospital stays than normal weight individuals during the period 1971-1975. During the period 1976-1980, their stays were 60 percent, 94 percent, and 218 percent longer, respectively, than normal-weight individuals. For the period 1981-1985, their stays were two to three times longer, and from 1986 to 1982, their stays were 36 percent, 60 percent and 231 percent longer, respectively. With the exception of the final followup period (1986-1992), underweight individuals had longer hospital stays than normal-weight individuals, probably due to illness-induced weight loss.

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