Chapter 18: Abdominal Wall Hernia

The Burden of Digestive Diseases in the United States

James E. Everhart, M.D., M.P.H.

Abdominal wall hernias (AWH) are coded by their anatomical location (direct and indirect inguinal, femoral, and umbilical, plus other or unspecified) and subcoded by complication (obstruction, with or without gangrene) in ICD-10. Coding was different in ICD-9, which had an odd combination of location and complication (Appendix 1). However, the individual codes match up fairly well between the two editions.

The large majority of AWH are inguinal hernias, which frequently occur as a result of incomplete closure of the inguinal canal in male infants. Hence, there was a substantial number of ambulatory care visits among children and more than twice the rate among males as females in 2004 (Table 1). However, among adults, the rate of visits increased progressively with age. Whites had a higher rate than blacks. Rates have not changed appreciably since 1975.14 AWH was the third leading cause of ambulatory care visits in 2004, after GERD and constipation. Rates of hospital discharges with AWH were higher among blacks and there was little difference by sex.

The definitive treatment of AWH is by surgical repair. Because most repairs no longer require overnight hospitalization, the rate of hospitalizations has declined substantially, largely over a 10-year period between 1983 and 1993 (Figure 1). This decline was mostly accounted for by substantial reduction in the number of direct hernia repairs among males.15 The same decline did not occur among females, which may account for the similar discharge rates between males and females.

In 2004, more than 1,000 persons died with AWH as the underlying cause (Table 2). The large majority of deaths occurred among persons age 65 years and older. Mortality rates were similar for whites and blacks and for males and females. Mortality rates declined between 1979 and the mid-1990s for AWH as underlying cause and more substantially as underlying or other cause (Figure 2). Mortality rates were then stable through 2004.

Because AWH is primarily a surgical condition, prescriptions filled at retail pharmacies captured through the Verispan database (Appendix 2) may not have captured the extent and nature of medication use for these conditions. In 2004, there were an estimated 3.7 million retail prescriptions filled, at a cost of $59.5 million. More than 97 percent of these prescriptions were for analgesics, with the rest for antimicrobial agents.

References

Table 1. Abdominal Wall Hernia: Number and Age-Adjusted Rates of Ambulatory Care Visits and Hospital Discharges With First-Listed and All-Listed Diagnoses by Age, Race, and Sex in the United States, 2004

Source: National Ambulatory Medical Care Survey (NAMCS) and National Hospital Ambulatory Medical Care Survey (NHAMCS) (3-year average, 2003–2005), and Healthcare Cost and Utilization Project Nationwide Inpatient Sample (HCUP NIS)

Demographic Characteristics Ambulatory Care Visits First-Listed Diagnosis Number in Thousands Ambulatory Care Visits First-Listed Diagnosis Rate per 100,000 Ambulatory Care Visits All-Listed Diagnosis Number in Thousands Ambulatory Care Visits All-Listed Diagnosis Rate per 100,000 Hospital Discharges First-Listed Diagnosis Number in Thousands Hospital Discharges First-Listed Diagnosis Rate per 100,000 Hospital Discharges All-Listed Diagnosis Number in Thousands Hospital Discharges All-Listed Diagnosis Rate per 100,000
AGE (Years)
Under 15
160 264 417 685 5 8 24 40
AGE (Years)
15–44
1,113 885 1,278 1,016 29 23 65 52
AGE (Years)
45–64
1,492 2,111 1,804 2,552 60 84 124 176
AGE (Years)
65+
976 2,686 1,288 3,545 69 189 158 435
Race
White
3,347 1,348 4,223 1,703 130 51 290 115
Race
Black
287 858 437 1,275 17 54 47 142
Sex
Female
1,056 681 1,526 987 86 54 194 121
Sex
Male
2,686 1,902 3,261 2,317 75 56 177 132
Total 3,742 1,274 4,787 1,630 163 55 372 127

Figure 1. Abdominal Wall Hernia: Age-Adjusted Rates of Ambulatory Care Visits and Hospital Discharges With All–Listed Diagnoses in the United States, 1979–2004

The rate of ambulatory care visits over time (age-adjusted to the 2000 U.S. population) is shown by 3-year periods (except for the first period which is 2 years), between 1992 and 2005 (beginning with 1992–1993 and ending with 2003–2005). Ambulatory care visits per 100,000 increased from 1,340 in 1992-1993 to 1,607 in 2003-2005. The rate of hospitalization has declined substantially, largely over a 10-year period between 1983 and 1993. Hospitalizations per 100,000 decreased from 391 in 1979 to 111 in 1995 and then remained stable through 2004 when the rate was 110.
Source: National Ambulatory Medical Care Survey (NAMCS) and National Hospital Ambulatory Medical Care Survey (NHAMCS) (averages 1992–1993, 1994–1996, 1997–1999, 2000–2002, 2003–2005), and National Hospital Discharge Survey (NHDS)

Table 2. Abdominal Wall Hernia: Number and Age-Adjusted Rates of Deaths and Years of Potential Life Lost (to Age 75) by Age, Race, and Sex in the United States, 2004

Source: Vital Statistics of the United States

Demographic Characteristics Underlying Cause Number of Deaths Underlying Cause Rate per 100,000 Underlying Cause Years of Potential Life Lost in Thousands Underlying or Other Cause Number of Deaths Underlying or Other Cause Rate per 100,000
AGE (Years)
Under 15
10 0.0 0.7 21 0.0
AGE (Years)
15–44
43 0.0 1.6 70 0.1
AGE (Years)
45–64
197 0.3 3.8 384 0.5
AGE (Years)
65+
922 2.5 0.8 1,624 4.5
Race
White
1,015 0.4 5.3 1,815 0.7
Race
Black
133 0.5 1.5 246 0.9
Sex
Female
670 0.4 3.2 1,132 0.6
Sex
Male
502 0.4 3.7 967 0.8
Total 1,172 0.4 6.9 2,099 0.7

Figure 2. Abdominal Wall Hernia: Age-Adjusted Rates of Death in the United States, 1979–2004

Mortality rates declined between 1979 and the mid-1990s as underlying cause and more substantially as underlying or other cause, and were then stable through 2004. Underlying-cause mortality per 100,000 decreased from 0.61 in 1979 to 0.39 in 2004. All-cause mortality per 100,000 decreased from 1.68 in 1979 to 0.83 in 1991, and was 0.69 in 2004.
Source: Vital Statistics of the United States
Last Reviewed January 2008