Reduced frequency of wheezing respiratory illness in infants with perinatal human immunodeficiency virus-type 1 infection: a model for immunologic and inflammatory mechanisms of airway obstruction?

Respiratory symptoms in people living with HIV and the effect of antiretroviral therapy: a systematic review and meta-analysis

Background

Antiretroviral therapy (ART) has significantly altered the pattern of acute and chronic HIV-related disease. However, it is not clear what this means in terms of respiratory symptoms. We sought to investigate the association between HIV status and respiratory symptoms and how these have changed with the availability of ART.

Methods

We searched Cochrane, Medline and Embase databases for studies published between 1946 and August 2015 comparing the prevalence of respiratory symptoms in populations with and without HIV infection. We undertook random effects meta-analysis of the main symptoms reported. We studied heterogeneity and completed sensitivity analyses and funnel plots.

Results

From 5788 unique references identified, 24 papers provided relevant data: 18 documented the prevalence of cough and 11 examined the prevalence of breathlessness among other symptoms reported. Compared with the HIV negative, people living with HIV (PLWH) were more likely to have respiratory symptoms with pooled ORs for the prevalence of cough of 3.05 (95% CI 2.24 to 4.16) in resource-limited populations without access to ART; 2.18 (1.56 to 3.18) in resource-rich populations without access to ART and 1.11 (0.99 to 1.24) in resource-rich populations with access to ART. In resource-rich settings, although the availability of ART was associated with a reduction in the difference between HIV-positive and HIV-negative individuals, PLWH were more likely to report breathlessness, OR 1.39 (95% CI 1.11 to 1.73).

Conclusions

Respiratory symptoms are more common in PLWH than controls. This association persists although at a reduced level in populations with access to ART.

Respiratory impedance in healthy unsedated South African infants: effects of maternal smoking

Background and objective

Non-invasive techniques for measuring lung mechanics in infants are needed for a better understanding of lung growth and function, and to study the effects of prenatal factors on subsequent lung growth in healthy infants. The forced oscillation technique requires minimal cooperation from the individual but has rarely been used in infants. The study aims to assess the use of the forced oscillation technique to measure the influence of antenatal exposures on respiratory mechanics in unsedated infants enrolled in a birth cohort study in Cape Town, South Africa.

Methods

Healthy term infants were studied at 6–10 weeks of age using the forced oscillation technique. Respiratory impedance was measured in the frequency range 8–48 Hz via a face mask during natural sleep. Respiratory system resistance, compliance and inertance were calculated from the impedance spectra.

Results

Of 177 infants tested, successful measurements were obtained in 164 (93%). Median (25–75%) values for resistance, compliance and inertance were 50.2 (39.5–60.6) cmH₂O.s.L⁻¹, 0.78 (0.61–0.99) mL.cmH₂O⁻¹ and 0.062 (0.050–0.086) cmH₂O.s².L⁻¹, respectively. As a group, male infants had 16% higher resistance (P = 0.006) and 18% lower compliance (P = 0.02) than females. Infants whose mothers smoked during pregnancy had a 19% lower compliance than infants not exposed to tobacco smoke during pregnancy (P = 0.005). Neither maternal HIV infection nor ethnicity had a significant effect on respiratory mechanics.

Conclusions

The forced oscillation technique is sensitive enough to demonstrate the effects of tobacco smoke exposure and sex in respiratory mechanics in healthy infants. This technique will facilitate assessing perinatal influences of lung function in infancy.

Increased risk of asthma and atopic dermatitis in perinatally HIV-infected children and adolescents

The incidence of asthma and atopic dermatitis (AD) was evaluated in HIV-infected (n = 451) compared to HIV-exposed (n = 227) but uninfected (HEU) children and adolescents by abstraction from clinical charts. Asthma was more common in HIV-infected compared to HEU children by clinical diagnosis (25% vs. 20%, p = 0.101), by asthma medication use, (31% vs. 22%, p = 0.012), and by clinical diagnosis and/or medication use, (34% vs. 25%, p = 0.012). HIV-infected children had a greater risk of asthma compared to HEU children (HR = 1.37, 95% CI: 1.01 to 1.86). AD was more common in HIV-infected than HEU children (20% vs. 12%, p = 0.009)) and children with AD were more likely to have asthma in both cohorts (41% vs. 29%, p = 0.010). HIV-infected children and adolescents in this study had an increased incidence of asthma and AD, a finding critical for millions of HIV-infected children worldwide.

Association between HLA inheritance and asthma medication use in HIV positive children

This study's purpose was to determine whether asthma medication use in HIV positive children is associated with human leukocyte antigen (HLA) alleles. We reviewed HLA and medication data collected during the Women and Infants Transmission Study for 124 HIV positive children and their mothers. Analysis revealed that HLA-A68 (P = 0.006) was independent and predictive for time to first asthma medication use. There was a preventive association of Cw6 (P = 0.008) with asthma time. Highly active antiretroviral therapy (HAART) was also associated with time to first asthma medication use (P = 0.05). HLA alleles may modulate risk of developing a need for asthma medications and seem to function independently of the actions of HAART therapy.

Is there a link between wheezing in early childhood and adverse birth outcomes? A systematic review

We aimed to provide a summary of the existing published knowledge on the association between adverse birth outcomes and the development of wheezing during the first two years of life. We carried out a systematic review of epidemiological studies within the MEDLINE database. Epidemiological studies on human subjects, published in English, were included in the review. A comprehensive literature search yielded 72 studies for further consideration. Following the application of the eligibility criteria we identified nine studies. A positive association and an excess risk of wheezing during the first two years of life were revealed for adverse birth outcomes.

Increased incidence of asthma in HIV-infected children treated with highly active antiretroviral therapy in the National Institutes of Health Women and Infants Transmission Study

BACKGROUND

Immunoreconstitution of HIV(+) patients after treatment with highly active antiretroviral therapy (HAART) appears to provoke inflammatory diseases.

OBJECTIVE

We sought to determine whether HIV(+) children receiving HAART (HIV(+) HAART(+)) have a higher incidence of asthma than HIV(+) children not receiving HAART (HIV(+) HAART(-)).

METHODS

Two thousand six hundred sixty-four children (193 HIV(+) and 2471 HIV(-) children) born to HIV(+) women were evaluated for the incidence and prevalence of asthma (ie, asthma medication use) and change of CD4(+) T-cell percentage with time.

RESULTS

The HIV(+) HAART(+) children had higher CD4(+) T-cell percentages, lower CD8(+) T-cell percentages, and lower viral burdens than the HIV(+) HAART(-) children (P < or = .05 to P < or = .01). The cumulative incidence of asthma medication use in HIV(+) HAART(+) children at 13.5 years increased to 33.5% versus 11.5% in HIV(+) HAART(-) children (hazard ratio, 3.34; P = .01) and was equal to that in the HIV(-) children. In children born before the HAART era, the prevalence of asthma medication use for HIV(+) HAART(+) children at 11 years of age was 10.4% versus 3.8% for HIV(+) HAART(-) children (odds ratio, 3.38; P = .02) and was equal to that of the HIV(-) children. The rate of change of CD4(+) T cells around the time of first asthma medication for HIV(+) HAART(+) versus HIV(+) HAART(-) children was 0.81%/y versus -1.43%/y (P = .01).

CONCLUSION

The increased incidence of asthma in HIV(+) HAART(+) children might be driven by immunoreconstitution of CD4(+) T cells.