Self-reported Physical Health Practices and Health Care Utilization: Findings from ... care utilization data from the 1977 National Health Interview Survey.
Self-reported Physical Health Practices and Health Care Utilization: Findings from the National Health Interview Survey HARRY P. WETZLER, MD, MSPH, Abstract: Cross-sectional physical health practice and health care utilization data from the 1977 National Health Interview Survey were analyzed. After adjusting for the effects of age, sex, race, income, education, and marital status, there were significant relationships between hours of sleep and both doctor visits and hospital
days; increased physical activity was associated with fewer doctor visits. Prospective intervention studies are needed to determine whether changes in health practices will lead to decreased utilization. (Am J Public Health 1985; 75:1329-1330.)
Introduction In 1972, Belloc and Breslow' reported a positive relationship between seven health practices and a measure of physical health status using data obtained by the Human Population Laboratory (HPL) of Alameda County, California. The seven physical health practices included: adequate rest, exercise, eating breakfast, no snacking, proper body weight, use of alcohol in moderation, and no smoking. A second paper2 described an inverse correlation between the seven health practices and mortality over five and one-half years. In 1980, Breslow and Enstrom3 extended the mortality follow-up to nine and one-half years with similar findings. That same year, Wiley and Camacho4 published a nine-year follow-up where they found a positive relationship between five of the practices and future health. Eating breakfast and snacking were not found to be correlated with subsequent health. We sought to examine the possible association between health practices and health care utilization in a national sample.
Methods Data were obtained from the Health Interview Supplemental Record Public Use Tape for the 1977 National Health Interview Survey (NHIS) conducted by the National Center for Health Statistics (NCHS). There were 22,842 respondents ranging in age from 20 to 99. The independent variables included seven self-reported physical health practices: amount of sleep, frequency of eating breakfast, frequency of eating between meals (snacking), relative body weight, physical activity change, cigarette smoking, and alcohol consumption. The categories for each health practice are listed in Table 1. Alcoholic beverage consumption was summarized as the total number of drinks per sitting and the number of drinks each month. An index of health practices was calculated by transforming each practice into a dichotomous variable using From the Department of Preventive Medicine and Biometrics, Hebert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD. Address reprint requests to Harry P. Wetzler, MD, MSPH, Chief, Standards Research and Development, Department of Defense Medical Examination Review Board, USAF Academy, Colorado Springs, CO 80840. This paper, submitted to the Journal February 14, 1985, was revised and accepted for publication May 6, 1985.
AJPH November 1975, Vol. 75, No. 11
DAVID F. CRUESS, PHD definitions developed in the HPL studies.' Scores on the index ranged from zero to seven. The dependent variables were the number of doctor visits in 12 months, the number of short-stay hospital days in the past 12 months, and the number of dental visits in the last AND
two weeks. The number of dental visits in two weeks was multiplied by 26 to provide an estimate of annual estimates (suitable only for the aggregate analyses used in this paper). Age, sex, race, income, education, and marital status were included as covariates. The ANOVA procedure of the Statistical Package for the Social Sciences6 was used to analyze the relationship between the physical health practices and utilization variables. The responses were weighted to make the sample representative of the overall US adult population using a factor on the NCHS tape. Approximately 10 per cent of the responses for each health practice were "Unknown" or "Other" (which were both coded as missing values and the respondents were excluded from the analysis). The total proportion of missing responses for the seven health practice index was 15 per cent. Three-fifths of the non-respondents were males and slightly more (14.6 per cent vs 11.2 per cent) were nonWhites. The non-respondents had slightly more education but less income than the respondents. Health practice nonrespondents reported significantly more hospital days but fewer dental visits than the respondents.
Results The adjusted averages for each category of utilization by health practice are listed in Table 1. There were moderate relationships between doctor visits and the sleep and physical activity practices. Those who slept seven to eight hours per day also reported fewer hospital days. In addition, those consuming five or more drinks at a sitting reported fewer hospital days. The only difference in dental visits occurred for cigarette smoking where the never smokers reported fewer visits. There was a strong consistent relationship between the index of health practices and doctor visits and hospital days. Utilization regularly declined as the number of favorable practices increased. No such association existed for dental visits.
Discussion
Nonresponse bias is a concern in any survey research. In this study, health practice respondents reported fewer hospital days and more dental visits as well as more education. These findings certainly imply a response differential that may be socially based and would make generalization of the results hazardous. In addition, the issue of valid selfreporting is important for both the health practice independent variables and the utilization dependent variables. Selfreports of alcohol consumption,7 smoking,8 and exercise9 have been questioned as to both validity and reliability. Conversely, self-reported body weights have been found to be generally accurate.'0 1 329
PUBLIC HEALTH BRIEFS TABLE 1-Averag Adjusted Annual Doctor V1*lts, Hospital Days and Dental Visits by Sev#n Physical Health Practices and the Index of Health Practices
Health Practices Hours of Sleep 6 or less 7or8 9 or moro Eating Breakfast Every Day Sometimes Rarely or Never Eating Snacks Rarely or Never Sometimes Every Day Physicbl Activity More Active Same Less Active Relative Body Weight* -10% or iess -5 to -9.9% -4.9 to +4.9% +5 to 9.9%h +Io to 19.9%/0 +20 to 29.9% +30°h or more Alcohol Drinks at One Sitting"
None 1-4
5+ Alcoholic Drinks per Month***
0
1-8 9-16
17-30 31-45 46+
Doctor Visits
Hospital Days
Dental Visits
4.92 3.81 4.79
1.50 1.13 1.94
1.92 1.62 1.56
4.22 4.35 3.99
1.36 1.34 1.25
1.69 1.58 1.72
4.14 4.00 4.32
1.32 1.27 1.29
1.67 1.53
3.41 3.77 8.12
0.80 1.09 3.87
1.78 1.62 1.62
4.60 4.01 4.00 3.99 3.78 4.45 4.69
1.82 1.17 1.42 1.36 0.96 1.22 1.48
1.64 1.68 1.66 1.83 1.73
4.58 3.97 3.73
1.73 1.23 1.11
1.35 1.82 1.70
4.80 4.05 4.06 3.72 3.45 3.57
1.71 1.35 0.91 1.03
0.89
1.46 1.77 1.94 1.58 2.00 1.77
4.16 4.39 4.28
1.20 1.48 1.38
1.51 2.03 1.72
5.68 4.60 4.21 3.96 3.61 3.16
2.23 1.57 1.37 1.19 0.88
1.91 1.74 1.89 1.70 1.37 1.76
0.65
1.80
1.67
1.69
Cigarette Smoking Never Former Present Index of Health Practices 0-2 3 4 5 6 7
0.96
*Relative body weight was determined accordirt to the weight for height tables published by the Metropolitan Lie Insurance Company. "The drinks per sitting figure was the sum of the numbers of drinks at one sitfing for wine, beer, and liquor. *"The number of drinks per month was calculdted -by rhultiplyi,ng the frequency of consuming a beverage (three or more times per week" was equated to five times a week, "Once or twice a week" became 1.5 times a week, and "Occasionally" was coded as 0.25 tnies a week) by the usual number of drinks at one sitting to determine the number of dnnks per week for the beverage (wine, beer, or liquor). the weekly numbets for the thrte beverages were then added and muitiplied by four to obtain the number of drinks consuniied each month.
Although the relationships between the physical health practices and utilization were not impressive for the most part, the trends for hours of sleep, physical activity, relative body weight, and cigarette smoking support the association of lower utilization with better health practices. The rela-
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tionship between alkohol consumption and utilization suggests that non-drinkers have more physician visits and hospital days, and moderate drinkers have a lower mortality and better health'2 than heavy drinkers or non-drinkers. Only a few studies have attempted to relate health practices and health care utilization. Pope'3 reported a general tendency for higher levels of physical activity to be associated with lower rates of medical contacts but small and frequently negative relationships between smoking and the use of services. The strong and consistent linear relationship between the index of health practices and both physician visits and hospital days may imply a synergism of the practices. It is impossible to make causal inferences from crosssectional data. Indeed it is likely that the higher utilization among those with less physical activity may result from chronic conditions which preclude activity and result in higher utilization. Prospective intervention studies are needed to determine whether health practice changes will result in decreased utilization. ACKNOWLEDGMENTS This work was supported by the Uniformed Services University of the Health Sciences Research Grant No. R08734. The opinions and assertions contained herein are the private ones of the authors and are not to be construed as official or reflecting the views of the Uniformed Services University of the Health Sciences or the Department of Defense. An earlier version of this paper was presented at the Nineteenth Annual Meeting of the Society of Prospective Medicine, October 28, 1983.
REFERENCES 1. Belloc NB, Breslow L: Relationship of physical health status and health practices. Prev Med 1972; 1:409-421. 2. Belloc NB- Relationship of health practices and mortality. Prev Med 1973; 2:67-81. 3. Breslow L, Enstrom JE: Persistence of health habits and their relationship to mortality. Prev Med 1980; 9:469-483. 4. Wiley JA, Camacho TC: Life-style and future health: evidence from the Alameda County Study. Prev Med 1980; 9:1-21. 5. Metropolitan Life Insurance Company: New weight standards for men and women. Stat gull Metropol Life Insur Co 1959; 40:1-4. 6. Nie NH, Hull CH, Jenkins JG, Steinbrenner K, Bent DH: SPSS, Statistical Package for the Social Sciences, 2nd Ed. New York: McGrawHill, 1975. 7. Goodstadt MS, Cook G, Gruson V: The validity of reported drug use: the randomized response technique. Int J Addict 1978; 13:359-367. 8. Vogt TM, Selvin S, Widdowson G, Hulley St: Expired air carbon monoxide and serum thiocyanate as objective measures of cigarette exposure. Am J Public Ijealth 1977; 67:545-549. 9. Dunton S: Evaluating a risk reduction program: Well Aware About Health, a controlled clinical trial of health assessment and behavior modification. In: Faber MM, Reinhardt AM (eds): Promoting Health through Risk Reduction. New York: Macmillan, 1982. 10. Stunkard AJ, Albaum J: The accuracy of self-reported weights. Am J Clin Nutr 1981; 34:1593-1599. 11. LaPorte RE, Cresanta JL, Kuller LH: The relation of alcohol to coronary heart disease and mortality: implications for public health policy. J Public Policy 1980; 1:198-223. 12. Turner TB, Bennett VL, Hernandez H: The beneficial side of moderate alcohol use. Johns Hopkins Med J 1981: 148:53-63. 13. Pope CR: Life-styles, health status and medical care utilization. Med Care 1982; 20:402413.
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