Table 2.
Risk factors for anemia (N = 10,959 became anemic)
| Characteristics | Hgb < 11/person-months | Univariate HR (95% CI) | P value | Multivariate* HR (95% CI) | P value |
|---|---|---|---|---|---|
| Gender | |||||
| Female | 7,253/84,293 | Ref | – | Ref | – |
| Male | 3,706/44,900 | 0.57 (0.55, 0.60) | < 0.0001 | 0.55 (0.52, 0.57) | < 0.0001 |
| Age group, years | |||||
| < 30 | 2,097/26,574 | Ref | < 0.0001∥ | Ref | < 0.0001¶ |
| 30 to < 40 | 4,735/56,887 | 0.86 (0.82, 0.91) | 1.06 (1.00, 1.11) | ||
| 40 to < 50 | 2,759/30,986 | 0.80 (0.75, 0.84) | 1.15 (1.08, 1.22) | ||
| 50+ | 1,281/13,627 | 0.87 (0.81, 0.93) | 1.23 (1.14, 1.32) | ||
| Marital status | |||||
| Married/cohabiting | 5,022/62,504 | Ref | < 0.0001¶ | Ref | 0.007¶ |
| Widowed/divorced/separated | 800/8,522 | 1.27 (1.18, 1.37) | 0.99 (0.92, 1.07) | ||
| Single | 2,924/32,074 | 1.23 (1.17, 1.28) | 1.04 (1.00, 1.09) | ||
| District | |||||
| Ilala | 2,665/28,650 | Ref | < 0.0001¶ | Ref | < 0.0001¶ |
| Kinondoni | 4,740/59,414 | 0.98 (0.94, 1.03) | 1.15 (1.09, 1.21) | ||
| Temeke | 3,530/41,061 | 1.94 (1.85, 2.04) | 1.59 (1.51, 1.68) | ||
| BMI group, kg/m2§ | |||||
| < 18.5 | 1,860/12,981 | 1.66 (1.58, 1.75) | < 0.0001∥ | 1.52 (1.44, 1.60) | < 0.0001∥ |
| 18.5 to < 25 | 6,056/68,339 | Ref | Ref | ||
| 25.0 to < 30 | 2,090/31,300 | 0.79 (0.75, 0.83) | 0.76 (0.72, 0.80) | ||
| 30+ | 953/16,572 | 0.72 (0.67, 0.77) | 0.66 (0.61, 0.70) | ||
| WHO HIV disease stage§ | |||||
| I | 1,603/21,398 | Ref | < 0.0001¶ | Ref | < 0.0001¶ |
| II | 2,827/38,449 | 1.17 (1.10, 1.24) | 1.08 (1.02, 1.15) | ||
| III | 5,374/60,209 | 1.40 (1.32, 1.48) | 1.15 (1.08, 1.22) | ||
| IV | 1,155/9,136 | 2.61 (2.41, 2.82) | 1.93 (1.78, 2.09) | ||
| CD4 count, cells/μL§ | |||||
| < 50 | 1,488/7,530 | 3.02 (2.84, 3.21) | < 0.0001∥ | 2.47 (2.31, 2.64) | < 0.0001∥ |
| 50 to < 200 | 3,351/26,759 | 2.02 (1.93, 2.11) | 1.78 (1.69, 1.87) | ||
| 200+ | 6,120/95,427 | Ref | Ref | ||
| Previous ART use | 1,302/18,732 | 0.61 (0.57, 0.64) | < 0.0001 | 0.85 (0.80, 0.81) | < 0.0001 |
| TB history | 2,190/22,861 | 0.93 (0.88, 0.97) | 0.002 | 0.97 (0.93, 1.01) | 0.16 |
| Oral candidiasis§ | 240/2,440 | 1.96 (1.76, 2.18) | 0.0001 | 2.33 (2.04, 2.65) | < 0.0001 |
| Diarrhea§ | 355/3,475 | 2.78 (2.45, 3.17) | < 0.0001 | 1.75 (1.57, 1.95) | < 0.0001 |
| ALT > 120 U/L§ | 151/1,752 | 1.47 (1.25, 1.73) | < 0.0001∥ | 1.38 (1.17, 1.62) | < 0.0001¶ |
| Hepatitis B surface antigen§ | 854/9,819 | 1.09 (1.02, 1.17) | 0.22 | 1.08 (1.00, 1.16) | 0.04 |
| Creatinine > 1.2 mmol/L§ | 1,481/16,757 | 1.02 (0.96, 1.07) | < 0.0001∥ | 1.03 (0.98, 1.09) | 0.03∥ |
| Kaposi's sarcoma§ | 18/37 | 4.46 (2.81, 7.09) | < 0.0001 | 3.86 (2.43, 6.15) | 0.0001 |
| On septrin prophylaxis§ | 1,962/13,793 | 1.78 (1.69, 1.87) | < 0.0001 | 1.50 (1.42, 1.58) | < 0.0001 |
| Currently being treated for TB§ | 709/5,830 | 1.35 (1.25, 1.46) | < 0.0001 | 1.19 (1.09, 1.29) | < 0.0001 |
| Taking a multivitamin§ | 4,802/57,542 | 0.99 (0.95, 1.03) | 0.66 | ||
| On ART†‡§ | 6,389/69,974 | 1.76 (1.69, 1.84) | < 0.0001 | 1.40 (1.33, 1.48) | < 0.0001¶ |
| Regimen contains AZT†‡§ | 3,569/37,047 | 1.49 (1.42, 1.57) | < 0.0001¶ | 1.43 (1.36, 1.51) | < 0.0001¶ |
| Not on ART | 4,570/59,219 | 0.70 (0.66, 0.74) | 0.70 (0.67, 0.74) | ||
| Other regimens (non-AZT) | 2,820/32,926 | Ref | Ref | ||
| Regimen contains EFV†‡§ | 2,898/25,211 | 1.30 (1.24, 1.37) | < 0.0001¶ | 1.17 (1.12, 1.24) | < 0.0001¶ |
| Not on ART | 4,570/59,219 | 0.64 (0.61, 0.67) | 0.71 (0.68, 0.75) | ||
| Other regimens (non-EFV) | 3,491/44,763 | Ref | Ref | ||
| ART regimen†‡§ | |||||
| D4T, 3TC, NVP | 2,372/27,645 | Ref | < 0.0001¶ | Ref | < 0.0001¶ |
| D4T, 3TC, EFV | 273/1,682 | 1.10 (0.97, 1.25) | 0.95 (0.83, 1.07) | ||
| AZT, 3TC, NVP | 1,050/15,461 | 1.53 (1.42, 1.65) | 1.45 (1.35, 1.56) | ||
| AZT, 3TC, EFV | 2,519/21,586 | 1.52 (1.44, 1.61) | 1.35 (1.28, 1.43) | ||
| TDF, FTC, EFV | 106/1,943 | 1.22 (1.01, 1.49) | 1.19 (0.98, 1.44) | ||
| Other | 69/1,656 | 1.26 (0.99, 1.60) | 1.30 (1.02, 1.65) | ||
| Not on ART | 4,570/59,219 | 0.71 (0.67, 0.75) | 0.79 (0.75, 0.84) | ||
ALT = alanine aminotransferase; ART = antiretroviral treatment; AZT = zidovudine; BMI = body mass index; CI = confidence interval; D4T = stavudine; EFV = efavirenz; TDF = tenofovir; FTC = emtricitabine; Hgb = hemoglobin; HIV = human immunodeficiency virus; NVP = nevirapine; TB = tuberculosis; 3TC = lamivudine; WHO = World Health Organization.
Multivariate-adjusted hazard ratio from a proportional hazards model was adjusted for all variables in the univariate analysis with a P < 0.20.
ARTs were entered into the final model separately with all other significant variables, AZT regimen, EFV regimen, ART, and ART regimens.
Referent group for “ART regimen” is comparing each regimen to “D4T, 3TC, NVP.”
Time-varying covariates. Analysis performed using Andersen–Gill data structure with 340,137 observations during follow-up period.
Association was significantly nonlinear. P value corresponds for the test of overall significance.
P value corresponds to test for trend.