Food insecurity increases risk of death for patients taking HIV treatment in Canada

This article is more than 15 years old.

Patients taking HIV treatment in Vancouver, Canada, who are 'food insecure' have an increased risk of death, researchers report in the online edition of the Journal of Acquired Immune Deficiency Syndromes. The risk of death was especially high for food-insecure individuals who were of low weight.

“Our findings suggest that targeted food supplementation coupled with other measures to alleviate poverty should …be a priority among urban poor HIV-infected individuals in well-resourced settings,” comment the investigators.

There have been significant improvements in the health and life expectancy of HIV-positive patients since the advent of effective antiretroviral therapy. However, some groups of HIV-infected individuals, such as those from minority communities or patients with a history of drug or alcohol abuse, are less likely to access HIV treatment and care and have higher rates of illness and death.

Glossary

confounding

Confounding exists if the true association between one factor (Factor A) and an outcome is obscured because there is a second factor (Factor B) which is associated with both Factor A and the outcome. Confounding is often a problem in observational studies when the characteristics of people in one group differ from the characteristics of people in another group. When confounding factors are known they can be measured and controlled for (see ‘multivariable analysis’), but some confounding factors are likely to be unknown or unmeasured. This can lead to biased results. Confounding is not usually a problem in randomised controlled trials. 

body mass index (BMI)

Body mass index, or BMI, is a measure of body size. It combines a person's weight with their height. The BMI gives an idea of whether a person has the correct weight for their height. Below 18.5 is considered underweight; between 18.5 and 25 is normal; between 25 and 30 is overweight; and over 30 is obese. Many BMI calculators can be found on the internet.

detectable viral load

When viral load is detectable, this indicates that HIV is replicating in the body. If the person is taking HIV treatment but their viral load is detectable, the treatment is not working properly. There may still be a risk of HIV transmission to sexual partners.

hazard ratio

Comparing one group with another, expresses differences in the risk of something happening. A hazard ratio above 1 means the risk is higher in the group of interest; a hazard ratio below 1 means the risk is lower. Similar to ‘relative risk’.

hazard

Expresses the risk that, during one very short moment in time, a person will experience an event, given that they have not already done so.

Food insecurity is defined as “limited or uncertain availability of nutritionally adequate safe foods or the inability to acquire personally acceptable foods in socially acceptable ways.”

It has been associated with worse outcomes in a number of disease areas. Food insecurity has also been recognised as a factor contributing to the continued spread of HIV in resource-limited settings and to poorer outcomes amongst individuals living with HIV in such countries.

Moreover, food insecurity was independently associated with a detectable viral load in HIV-positive patients in San Francisco. However, the relationship between mortality and food insecurity amongst patients with HIV in industrialised countries has never previously been examined.

Therefore, researchers from the British Columbia Centre for Excellence in HIV/AIDS’ Drug Treatment undertook a study involving 1119 individuals.

The patients completed questionnaires assessing eight measures of food insecurity, and information was also obtained on non-accidental deaths.

The investigators also assessed the relationship between food insecurity, death and body mass index, and their statistical analysis took into account a number of potentially confounding factors such as CD4 cell count, education, housing status and HIV treatment history.

Almost half (48%) of patients reported food insecurity. Women and individuals of aboriginal descent were more likely to report food insecurity, and it was also associated with younger age, lower CD4 cell count, high viral load, fewer years of HIV treatment, a history of injecting drug use, lower education, and unstable housing.

Adherence was poorer amongst patients who were food insecure than it was amongst patients who reported food security (62% non-adherent vs 38%). Furthermore, the mortality rate due to non-accidental causes was twice as high amongst patients with food insecurity compared to food-secure individuals (22% vs 11%).

When the researchers took into account possible confounding factors, they still found that food insecure patients had a 50% increase in their risk of death (adjusted hazard ratio [AHR] = 1.51, 95% CI, 1.03 to 2.23).

The investigators’ analysis then considered the role of low body weight. They found that after controlling for all possible confounding factors, patients who were both food insecure and underweight (BMI below 18.5 m2) were almost twice as likely to die than patients who were neither food insecure nor underweight (AHR = 1.94, 95% CI, 1.10 to 3.40).

Finally, the researchers found that mortality rates were significantly elevated in food-insecure patients who were underweight (p

“We found that HAART-treated individuals who were food insecure were significantly more likely to die of non-accidental causes compared with individuals who were food secure,” write the investigators.

They stress that there was a very high prevalence of food insecurity in their study population, meaning that “the negative impacts of food insecurity on health outcomes may be experienced by a large proportion of urban poor HIV-infected individuals.”

The investigators conclude, “Novel interventions to alleviate food insecurity and poverty among urban poor individuals in resource-rich settings are needed to avoid clinical deterioration and excess mortality.”

They therefore recommend that “clinicians caring for HIV infected individuals may consider working in multidisciplinary teams that include both case managers and nutritionists. These teams can screen individuals for food insecurity and poor nutritional status, inquire about barriers to food access, and help individuals who are food insecure identify reliable sources of good quality food.”

References

Weiser SD et al. The association between food insecurity and mortality among HIV-infected individuals on HAART. J Acquire Immune Defic Syndr (online edition), 2009.