Research: Is obesity a barrier to Pap smear and mammography screening?

By: Olasupo A. Olagundoye, M.D.,
Linda Z. Nieman, Ph.D.,
Lee Cheng, M.D., M.S.

Joint Primary Care Fellowship
Department of Family and Community Medicine
University of Texas Medical School at Houston
Houston, Texas

Background

Literature suggests that overweight and obese women receive Pap smear and mammography screenings less often than normal-weight women. Contribu­tory factors to this difference may be due to physician attitudes and biases toward obese women or the reluctance of obese women to be screened because of self-esteem issues. In view of the rapidly increasing prevalence of obesity in the United States, the importance of preventive health screenings in this high-risk group of patients cannot be overemphasized.

Objective

To study whether obesity affects physicians’ adherence to recommended Pap smear and mammogram guidelines in a public health clinic setting.

Design

Retrospective medical chart review of female patients over a three-year period from June 2001 to May 2004. All charts were reviewed by a trained research assistant experienced in identifying documentation issues and assessing adherence to clinical practice guidelines. Chi-square analyses were used to examine the relationship between body mass index (BMI) and Pap smear and mammogram screening. Logistic regression model was used to control for factors that could affect Pap smear and mammogram screening such as the patient’s age, ethnicity, insurance status and chronic health disorders.

The pool of patients came from a public health clinic in the county hospital district. The patients were female, aged 18 to 65 years (Pap smear) and 40 to 70 years (mammogram) of African-American, Hispanic, Caucasian and other ethnic groups seen at Acres Home Community Health Center in Harris County Hospital District during the study period.

Results

Two hundred and eighty-six patients’ data were collected from medical charts.

The mean age of patients in the study was 51.44 ± 9.78 years. The study population was 38.8 percent African-American, 33.6 percent Hispanic, 15.8 percent Caucasian and 11.5 percent Asian. One hundred and ninety-two patients in the study had at least one chronic health problem. All the patients studied had access to the clinic by use of a gold card.

Compared to patients of normal weight (BMI 19 – 24.9), obese study patients (BMI > 30) were two times less likely to be offered Pap smear by physicians (OR 2.1; 95 percent CI, 1.1 – 4.1). Screening mammograms were twice less likely to be offered to overweight patients (BMI 25 – 29.9) (OR 2.8; 95 percent CI, 1.3 – 6.2) and three times less likely to be offered to obese patients (OR 3.2; 95 percent CI, 1.5 – 6.8) when compared to women that were normal weight. In addition, overweight and obese patients were twice less likely to be offered both Pap smear and mammogram screening (OR 2.5; 95 percent CI, 1.3 – 5.1), (OR 2.9; 95 percent CI, 1.5.7) respectively when compared to women that had normal weight.

The patients’ ages, ethnicities or histories of chronic health condition were not found to influence Pap smear or mammogram screening in a statistically significant way.

Conclusion

Overweight and obese patients are less likely to be offered cervical cancer screening with Pap smear and breast cancer screening by physicians in this public health clinic. There is an increasing trend of patients that are overweight and obese, so intervention is needed to ensure adherence to recommended female preventive screening guidelines in the public health clinic setting.

Discussion

The obesity epidemic has rapidly become a major public health issue in the United States. Current health statistics estimate that 66 percent of U.S. adults are overweight or obese. Unfortunately, women who are obese have significantly higher morbidity and mortality rates than non-obese women. Why is this the case? The medical literature suggests that overweight and obese women get breast and cervical cancer screening less often than those with normal weight. However, few studies have actually verified this lesser screening and most of these studies have only relied on patient recall.

Physicians may screen overweight and obese women less frequently during routine health care because the physicians must immediately address health issues other than prevention. In the same encounter, the physician may have to manage one or more chronic medical disorders such as type 2 diabetes mellitus, hypertension, coronary artery disease and degenerative arthritis. All of these problems, which demand substantial time to manage appropriately, are more prevalent in overweight and obese women.

Evidence shows that increased screening can make a difference in health outcomes. Indeed, routine Pap smear screening over the past few decades has led to the declining mortality from cervical cancer. Thus, it appears that physicians can extend the advances that routine screening offers to normal weight women, by consistently applying the same screening tests to overweight and obese women.

Unfortunately, our retrospective study, conducted in a public health clinic showed a declining trend in cervical and breast cancer screening offered by physicians to overweight female patients. As their body mass index (BMI) increased, obese women (BMI ≥ 30.0) were two times less likely to be offered Pap smear screening and three times less likely to be offered mammograms when compared to females of normal weight (BMI < 25.0).

We believe that several factors may have contributed to the screening differences in this study. First, physicians may have experienced an increased difficulty in performing the pelvic exams on obese female patients as compared to patients of normal weight. Second, physicians may have negative attitudes and/or biases towards overweight and obese patients. Third, patients may suffer from low self-esteem and a negative body image, making them unwilling to be examined. We cannot know if patients did not follow their doctors screening recommendations because we only counted the physicians who offered screening. We also do not know whether the patient’s beliefs about cancer screening differed from those of their physicians.

It is not surprising in this study that similar results are seen with both the pelvic examination and breast cancer screenings, since they are usually performed together as part of a routine well-women examination. We suggest that routine quality assurance measures will need to monitor the offering of cancer screening to all female patients. Particular attention should be given to female patients who are overweight or obese.