Delays and Continuation of Hospital Visits Among HIV-Infected Persons and AIDS Cases in Japan

This study attempts to clarify the distribution patterns of delay between HIV transmission and the first hospital visit among HIV-infected persons and AIDS cases in Japan except those infected through blood products. Such hospital visit patterns were analyzed, and the rates of reporting for HIV/AIDS surveillance among diagnosed HIV-infected persons and AIDS cases in hospitals were shown. From 1991 to 1997, a survey and subsequent follow-up were conducted among HIV-infected persons and AIDS cases diagnosed at 74 hospitals in Tokyo. The numbers of HIV-infected persons and AIDS cases were 590 and 208, respectively. The percentage of patients whose estimated date of HIV transmission was obtained ranged 23-41 % among Japanese and non-Japanese HIV-infected persons and AIDS cases. Among these patients, 28% to 86% showed a 3-year delay between HIV transmission and their first hospital visit. The rate of HIV-infected persons who continued to visit hospitals within 1 year after their first visit was 77% for Japanese and 45% for non-Japanese; among those after 1 year or more following their first hospital visit the rate was more than 80% among Japanese and over 70% among non-Japanese. The rate of reporting to HIV/AIDS surveillance among diagnosed HIV-infected persons and AIDS cases was 90% or more after 1994 in Japan. The delay between HIV transmission and the first hospital visit was suggested to be very long. Not a few patients stopped visiting hospitals after only a short time. Most diagnosed HIV-infected persons and AIDS cases were reported to the surveillance system of Japan. J Epidemiol, 2000 ; 10 : 65-70


MATERIALS AND METHODS
The survey and subsequent follow-up for the indicated HIVinfected persons and AIDS cases diagnosed at 74 selected hospitals in Tokyo were conducted during 1991-1997.The patients diagnosed in 1991 and before were registered in the year 1991, and the patients diagnosed from 1992 to 1997 were registered annually.Information on the patients obtained by physicians from the registration included hospital name, patient number (coded by each hospital), the date and diagnostic status (HIV or AIDS) of the first visit to the hospital, refer-rals by other hospitals, nationality, sex, date of birth, source of exposure to HIV infection, estimated date of HIV infection based on patient recall, and reporting to the WV/AIDS surveillance of the Ministry of Health and Welfare, Japan.In the subsequent follow-up, information on patients included current status (alive or dead), record of visiting the hospital and reasons for discontinuing visits (move to another hospital, departure from Japan or unknown reasons).Among patients who moved to other hospitals that were also included in this survey, their hospital visits were assumed to continue.
The number of patients registered was shown in Table 1.HIV-infected persons included 429 Japanese and 161 non-Japanese.AIDS cases included 147 Japanese and 61 non-Japanese.Transmission routes of HIV among Japanese and non-Japanese HIV-infected persons and AIDS cases were comprised of homosexual/bisexual contacts 31-60%, heterosexual contacts 26-54%, and other and unknown routes 10-26%.
For patients whose estimated date of HIV transmission was obtained, distribution patterns of the delay between HIV transmission and the first hospital visit were calculated.These distribution patterns were also calculated for patients not referred by other hospitals because such patients would have thus visited these other hospitals before making their first visit to ours.The continuation rates of visiting hospitals each year after the first hospital visit, and the reasons for discontinuing the visits were analyzed.The rates of reporting to HIV/AIDS surveillance were calculated.These analyses were conducted for Japanese and non-Japanese nationalities because there would be differences in medical care use between these 2 groups.

Delay between HIV transmission and the first hospital visit
The analysis of patients whose estimated date of HIV transmission was obtained was shown in Table 2. HIV-infected persons were 41% Japanese and 29% non-Japanese, while AIDS cases were 24% Japanese and 23% non-Japanese.There were small differences in the rates between patients with and without referral by other hospitals.
Distribution patterns of the delay between HIV transmission and the first hospital visit were shown in Figure 1.Among Japanese HIV-infected persons, such delay patterns were 36% in less than 1 year, 25% in 1-2 years, 9% in 2-3 years, and 28% in more than 3 years.Patients with delays of more than 3 years were 69% in Japanese AIDS cases, 37% in non-Japanese HIVinfected persons, and 86% in non-Japanese AIDS cases.There were small differences in the delay between patients with and without referral by other hospitals.

Continuation of hospital visits
The numbers of Japanese HIV-infected persons observed were 429 at the first hospital visit, 263 after 1 year, 187 after 2 years, and 125 after 3 years.The numbers of non-Japanese HIV-infected persons observed were 161 at the first visit, 56 after 1 year, 34 after 2 years, and 18 after 3 years.
The continuation status of visiting hospitals among HIVinfected persons each year after the first visit was shown in Figure 2.Among Japanese HIV-infected persons, 77% continued to visit hospitals within 1 year after their first visit.Other developments included death 2%, move to other hospitals 7%, departure from Japan 1%, and unknown reasons for discontinuing visits 14%.After 1 year or more following the first hospital visit, more than 80% of the patients continued to visit the hospitals.The mortality rate of patients increased with the years after the first visit.Inversely, there was an annual decrease in the percentage of patients whose reasons for discontinuing the visits were unknown.
Among non-Japanese HIV-infected persons, 45% continued to visit the hospitals within 1 year after their first visit.Other developments included death 1%, move to other hospitals 8%, departure from Japan 23%, and unknown reasons for discon-tinuing visits 24%.After 1 year or more following the first hospital visit, more than 70% of the patients continued to visit the hospital.The percentage of patients who departed Japan after I year or more following the first visit was as high as among those who departed Japan within the first year.The percentage of the patients whose reasons for discontinuing the visits were unknown after 1 year or more following the first visit, was lower than among those who stopped within the first year.

Reporting to HIV/AIDS surveillance
Rates of reporting to HIV/AIDS surveillance among diagnosed HIV-infected persons and AIDS cases were shown in Table 3.The reporting rates among HIV-infected persons were 91% among Japanese and 84% among non-Japanese, and those for AIDS cases were 90% among Japanese and 84% among non-Japanese.
Rates of reporting to HIV/AIDS surveillance each year after the first hospital visit were shown in Figure 3.The reporting rates among both HIV-infected persons and AIDS cases increased for both Japanese and non-Japanese, reaching 90% or more after 1994.

DISCUSSION
Our study subjects were HIV-infected persons and AIDS cases diagnosed at 74 selected hospitals in Tokyo up to the end of 1997.Institutions surveyed included leading hospitals for the treatment of HIV infection and AIDS in Tokyo.The numbers of HIV-infected persons reported to the HIV/AIDS surveillance of Japan by the end of 1997 were 1300 Japanese and 1190 non-Japanese 3), while AIDS cases numbered 758 Japanese and 298 non-Japanese.Although the numbers of our subjects in Table 1 did not strictly coincide with these figures, we considered that our subjects included the majority of HIV-Table 2. Proportions of patients whose estimated dates of HIV transmission were obtained.

ALL patients
Patients without referral by other hospitals Figure 1.Distribution pattern of the delay between HIV transmission and the first hospital visit.
Japanese HIV-infected persons Non-Japanese HIV-infected persons   infected persons and AIDS cases diagnosed in Tokyo.
Patients who delayed more than 3 years between HIV transmission and their first hospital visit accounted for 28-86% (calculated from patients whose estimated dates of HIV transmission were obtained), and they were 24-41% of all patients.Our data supported the idea that the delay was so long that promoting voluntary HIV testing and counseling for HIV-infected persons had become more necessary 2,5,6).
HIV-infected persons who discontinued hospital visits except for reasons of death, movement to other hospitals or departure from Japan, were 14-24% within 1 year after the first  11).In our study, the proportion of patients who discontinued hospital visits among non-Japanese HIV-infected persons was higher than among Japanese cases.These findings suggested that not a few patients soon stopped visiting hospitals, and that it was important to investigate the reasons in detail.The rate of reporting to the HIV/AIDS surveillance of Japan among diagnosed HIV-infected persons and AIDS cases reached more than 90% after 1994.Although the reporting was not complete, we considered the rates high enough to demonstrate a trend in HIV infection and AIDS 14,15).However, the coverage rates among all HIV-infected persons including cases not diagnosed would not be high because the delay between HIV transmission and the first hospital visit was very long 2,12,13) It is important to estimate and improve the coverage rates.
A major limitation in our study is the uncertainty of information, including estimated dates of HIV transmission and reasons for stopping hospital visits.Information on the estimated date of HIV transmission was obtained through interviews by physicians.If HIV transmissions originate from experiences such as blood transfusion and travel abroad, HIV-infected persons and AIDS cases might recall their estimated date of HIV transmission.In Japan, HIV transmissions through blood transfusions have been few because 100% of blood bags were screened for HIV after 1986 3,4).HIV transmissions in foreign countries among Japanese HIV-infected persons and AIDS cases were reported to be 19% or more 3).Although we failed to confirm the distribution patterns of delay between HIV transmission and the first hospital visit, it became clear that the delay was very long.Data on whether patients continued or discontinued their hospital visits were quite reliable, but the reasons for stopping the visits (e.g., departure from Japan or switching hospitals) were not so reliable because information was obtained from physician interviews.Although the distribution patterns of visiting hospitals may be biased, the suggestion that not a few patients soon discontinued their hospital visits may be valid.The information on reporting to HIV/AIDS surveillance was not confirmed by the surveillance data because the information did not include a patient's name and address, so individuals could not be identified 3).Although the rates of reporting to surveillance were not completely accurate, the general finding of high reporting rates would not be significantly affected.

Figure 2 .
Figure 2. Continuation status of visiting hospitals among HIV-infected persons by the year after the first visit.

Figure 3 .
Figure 3.Rates of reporting to HIV/AIDS surveillance.

Table 1 .
Number of subjects.

Table 3 .
Rates of reporting to HIV/AIDS surveillance.