Metabolic Syndrome in African American Female

Metabolic Syndrome in African American Female

Metabolic Syndrome in African American Female

Chapter 1: Introduction

Beginning in the early 1960's, rates of obesity in the US have been tracked in several cross-sectional national surveys, including the earliest survey from 1960-62, referred to as the National Health Examination Survey (NHES). Then, several successive surveys entitled the National Health and Nutrition Examination Survey (NHANES) were conducted in 1971-74 (referred to as NHANES I), 1976-80 (NHANES II), and 1988-94 (NHANES III). Later NHANES are simply referred to by the years in which they were conducted. (Adult participation in recommended levels of physical activity 2005)

The surveys are designed to sample around 5,000 adults and children each year from throughout the non-institutionalized civilian US population. (Bauman 2002) A questionnaire component of the survey includes information on demographics, socioeconomic status, dietary habits and other health related questions, while an examination component includes a medical and dental exam, physiological measurements and laboratory tests. Based on data from these surveys, between 1960 and 1994 there was little change in the prevalence of pre-obesity (defined by a body mass index (BMI) of 25.0-29.9 kg/m2), increasing only slightly from an age-adjusted prevalence of 30.5% in 1960-2 to 32.0% in 1988-1994 for those aged 20-74 years old. However, the increase in obesity, as defined by a BMI = 30 kg/m2, increased markedly from prevalence of 12.8% in 1960-2 to 22.5% in 1988-1994. Extreme obesity, as defined by a BMI = 40 kg/m2, also increased, from an age-adjusted prevalence of 0.8% in 1960-2 to 2.9% in 1988-94. In more recent years, the increasing trends have continued. The Centers for Disease Control and Prevention (CDC) reported that in the 2003-2004 NHANES assessment, 32.2% of US adults (=20 years old) were obese. This was almost 2% higher than the 1999-2000 NHANES survey, in which 30.5% of adults were classified as obese. (Trost 2006)

The increase originated primarily from a disproportionate increase in male obesity. In the 1999-2000 survey, 27.5% of males and 33.4% of females were obese, whereas in 2003- 2004, 31.1% of males and 33.2% of females were obese. During the same time period, high obesity rates (defined by a BMI = 40 kg/m2), while higher than the 1988-94 rates, have remained relatively constant. (Cleroux 2002) The earlier 1999-2000 survey reported 3.1% and 6.3% for men and women, respectively, and 2.8% and 6.9% in 2003-2004. Mexican Americans and non-Hispanic blacks have higher overall obesity rates than non-Hispanic whites, but this difference is due mostly to high rates found in females. While non-Hispanic white females had a 30.2% obesity rate in 2003-2004, 42.3% of Mexican-American females were obese, and 53.9% of non-Hispanic black females were obese. Clearly, obesity rates are influenced by race. (Byrne NM 2005)

Problem statement:

African American females have a higher prevalence of MMS risk factors and are at an increased risk for CVI mortality as compared with Caucasian women.. The association between physical activity and the MMS is unknown. Further, little is known about the relationships between moderate intensity physical ...