This paper provides evidence that homeless IDUs in San Francisco have a substantial unmet need for physical and oral health care services. High prevalence of health care needs among IDUs has been documented elsewhere. In Miami, Florida, Chitwood et al. found that 89% of IDUs reported a need for health care in the past 12 months, consistent with our finding that 82% of participants reported a need for physical care in the past 6 months.18
In our sample, 64% of participants reported a need for oral health care in the past 6 months, which is higher than a population of IDUs studied by Metsch et al. also in Miami (47% in the previous year).16
This higher prevalence of need in San Francisco may be in part because our whole sample of IDUs was homeless.
The low mean SF-12 Physical Component Score from our population is suggestive of the generally poor health status of homeless IDUs as compared to similarly aged and housed non-IDUs. Burdine et al. have documented that the SF-12 physical and mental health summary scores can serve as a useful measure of community health status when compared with more traditional means of measuring health status, for example through age-adjusted mortality rates or physician to population ratios.26
In this analysis, the SF-12 Physical Component Score was associated with health needs and care-seeking behavior.
The use of prescription opiates and benzodiazepines was associated with increased odds of needing frequent health care. Although our cross-sectional study design cannot evaluate causality, we hypothesize that participants with the greatest health needs may have sought prescription medications from healthcare providers. Alternatively, participants could have procured prescription opiates and benzodiazepines through unofficial channels in order to self-medicate for chronic pain, insomnia, or anxiety. Prescription opiate and benzodiazepine use were collinear with methadone treatment, suggesting the use of benzodiazepines in methadone treatment programs.
We found that many homeless IDUs reported needing frequent oral health care, and that having Medi-Cal insurance was significantly associated with increased odds of seeking oral health care. In July of 2009, the California State Assembly voted to cut the state’s adult dental coverage for Medi-Cal for an estimated savings of 109 million USD.29
However, in a report issued by the Oral Health Access Council, the authors argue that the short-term savings would likely evaporate quickly due to a loss of matching federal funds and increased emergency costs.30
Cuts to state Medicaid dental benefits have been associated with increased visits to emergency departments in previous studies.31
For example, when Maryland legislators eliminated Medicaid reimbursement of dentists for treatment of adults with dental emergencies in 1993, the University of Maryland’s emergency department experienced a 22% increase in dental visits by Medicaid clients.31
A reduction in preventive oral health care through the elimination of the statewide Medi-Cal dental program may lead to greater demands for acute dental care and an increased burden on emergency departments.
Participants had injected drugs for an average of 22 years. Bourgois has described the life circumstances of injection drug users as chaotic, interwoven with poverty, homelessness, violence, and addiction.32
Under these conditions where basic needs for food and shelter go unmet, injection drug users often wait until a crisis situation in order to seek oral health care.16
Moreover, heroin is a potent analgesic which may mitigate pain from all but the most severe oral health problems.10
HIV serostatus was not associated with the four outcome variables. Although some have estimated that almost all patients with HIV infection will contract oral diseases,33
we found no statistically significant associations between HIV serostatus and oral health. In our study of homeless injection drug users, decades of substance use, poverty, homelessness, and chronic health problems may predispose the entire population to poor oral health. While HIV may contribute to poor oral health, it is not independently statistically associated with greater oral health needs or care-seeking behavior. Furthermore, oral health problems may manifest in different stages of HIV infection; for example, oral candidiasis has been found to affect approximately one third of HIV-seropositive patients and more than 90% of patients with AIDS.34
We measured HIV seroprevalence via oral fluid testing but did not collect the laboratory data that would be necessary to assess disease progression.
Our study did not find a statistically significant association between methamphetamine use (injected or non-injected) and a frequent need for dental care. The concept of “Meth Mouth” has been popularized in the media. It refers to a belief that people who use methamphetamine suffer severe consequences in terms of poor oral health. In addition to poor lifestyle and hygiene practices of methamphetamine users, the drug has been hypothesized to contribute to reduced salivation (xerostomia), leading users to drink sugared sodas, which further exacerbates the risk for caries associated with salivary hypofunction.12–14
Persistent teeth-grinding (bruxism) and clenching have also been hypothesized to be more common among methamphetamine users and has been informally associated with tooth loss. The link between methamphetamine use and xerostomia has been questioned.13
Methamphetamine per se may not be responsible for poor oral health, as the effects of poverty, homelessness, and poor personal hygiene may have similar effects.
In bivariate analysis, we found that methadone treatment (maintenance or detoxification) was associated with increased odds of having sought health care. Increased rates of health care-seeking behavior among participants who had been on methadone treatment may be due to addiction treatment programs having on-site medical care or referring to such care. The lack of any bivariate association between methadone use and seeking oral care is suggestive of methadone maintenance and detoxification programs not providing the same level of linkages to oral health services as they do to non-dental medical care. Methadone treatment programs have been identified as a convenient and cost-effective venue for providing supplementary health and psychiatric services.35
Given the recent elimination of California’s adult dental coverage, methadone treatment centers could serve as important venues for non-emergency dental care.
Participants who reported a frequent need for dental care had lower odds of seeking oral health care than participants who did not report a frequent need for dental care. This counterintuitive finding may indicate that some participants with oral health problems may have sought care in the past and had their concerns addressed, while those who did not seek dental care continued to experience oral health problems. In other words, rather than oral health need predicting care-seeking behavior, care-seeking behavior predicted frequent oral health needs.
This study has several limitations that should be considered when interpreting its results. Participants were recruited using two distinct methodologies, targeted sampling in two neighborhoods and convenience sampling in another neighborhood. It is possible that the group recruited through convenience sampling was qualitatively different than the samples recruited through targeted sampling. However, our comparisons found few differences attributable to neighborhood or sampling design, and we controlled for these variables in analyses. In the analysis, health status was measured using the Short Form 12 Physical Component Score, which is a self-reported measure rather than a clinical assessment. The study lacked a validated oral health instrument, such as the Oral Health Impact Profile, which is a scaled index of the social impact of oral disorders.36
The primary outcomes in the study, the self-reported need for health and dental care, are subjective measures that could vary widely by individual. The study would have been much improved by clinical observations of physical and oral health, and expert opinion about the need for health or dental care. In future studies the authors hope to measure the number of decayed, missing, and filled teeth, a standard index that has been applied to homeless populations.37
A majority of participants reported seeking care “elsewhere.” In our study questionnaire we did not capture the specific sources of physical and oral health care, something that would be important to do in future studies. Study participants were asked about their care-seeking behaviors, but they were not asked if they received care. It would be misleading to assume that treatment-seeking resulted in treatment in every case. In future studies participants should be asked more detailed questions about the receipt of medical or dental treatment, including reasons why care was sought but not received. Further research should also explore the feasibility and acceptability of various oral health care preventive strategies. Finally, tobacco usage was not assessed, which is a potentially important confounding variable that should be accounted for in future studies.