Participants and procedures
The target population was people living with HIV, who were residents of Mizan-Aman, Ethiopia. The accessible population consisted of people living with HIV who were attending the HIV/ART clinic of Mizan-Tepi University Teaching Hospital (MTUTH), Aman, Ethiopia. The study was carried out for a period over two months from February 2018 to April 2018. Out of the total of 384 patients attending the HIV/ART clinic of MTUTH during these months, 300 eligible patients initially agreed and signed an informed consent form. Of the 300 eligible patients, 250 were finally selected using a simple random sampling method. Inclusion criteria were (i) age greater than 18 years and (ii) mentally stable, as determined by the attending clinicians. Finally, after removing the construct-level missing data, 244 samples were finally used for quantitative analysis (See Supplementary File attached). Three trained psychiatric nurses from the HIV/ART clinic of MTUTH performed the structured interview. The four words used as a part of recall memory test were translated into Amharic by a native Amharic language expert. These four words were native to local Ethiopian community and are used commonly in the Ethiopian cultural context.
The dementia task comprised 3 tasks which assessed memory recall, motor speed, and psychomotor speed. The first task involved a short-term memory task in which the participants were given four words to recall (dog, hat, bean, red) (translated into Amharic as wusha, kofiya, bakele, keyi) and were provided one second to say each word. Amharic translations of these four words are native to the local Ethiopian community and are used commonly (i.e. High-frequency words) in the Ethiopian cultural context. Though, it is plausible to think that the word length and number of syllables might play some role in recall memory, because the Amharic translation of these words are slightly longer and have slightly higher number of syllables. However, the associative retrieval mechanism facilitated by the high-frequency nature of these four words in both English and Amharic versions would have somewhat compensated the effect caused by the variation in the word lengths and number of syllables. The participants were then asked to remember the 4 words and told that they would be asked to recall the words again a bit later. This was followed by a motor speed task in which the patient was asked to tap the first two fingers of the non-dominant hand as quickly and as rapidly as possible. The maximum score for the motor task was 4 points, with specific performance levels being scored as follows: 4 = ≥ 15 taps in 5 seconds; 3 = 11-14 taps in 5 seconds; 2 = 7-10 taps in 5 seconds, 1 = 3-6 taps in 5 seconds; and 0 = 0-2 taps in 5 seconds with the maximum 4 points for motor speed task. Psychomotor speed was further assessed by asking the patient to perform several movements with the non-dominant hand as quickly as possible. Primarily the patients needed to clench their hand into a fist on a flat surface. They were then asked to put their hand flat on the surface with their palm down. Finally, they were asked to place their hand perpendicular to the flat surface while displaying the 5th digit. The whole task was demonstrated once to the patients who were then allowed to practice twice before starting the test. A maximum of 4 points was possible for the psychomotor task, with patient performance being scored as follows: 4 = 4 sequences in 10 seconds; 3 = 3 sequences in 10 seconds; 2 = 2 sequences in 10 seconds; 1 = 1 sequence in 10 seconds; and 0 = unable to perform the task. Finally, the patients were given the follow-up to the memory recall in which they were asked to recall the four words. For the words that were not recalled correctly the patients were prompted with a semantic clue as follows: animal (dog); a piece of clothing (hat); vegetable (bean); color (red). A maximum 4 points was possible for the memory recall task, with the scoring as follows: one point for each word spontaneously recalled, and 0.5 points for each correct answer after prompting. The final score was a sum of the three tasks, the maximum being 12. Patients who scored 10 points or less were referred for further dementia testing.
Measures
Sociodemographic measures
A questionnaire was used to gather sociodemographic information regarding the participants’ age, gender, marital status, religion, ethnicity, and occupation. The questionnaire also recorded information related to substance use: this included information about participants’ habitual use of commercial and indigenous alcoholic drinks such as tej, tella, areki, shamita, borde, and korefe, as well as about habits such as tobacco smoking, consumption of caffeinated drinks, and khat chewing (14)
Clinical measures
Data regarding participants’ clinical symptoms were also recorded. These included the patients’ current CD4 count, baseline CD4 count, viral load, duration on combination antiretroviral therapy regimen (cART), side effects from cART, opportunistic infections, duration since HIV diagnosis, other neuropsychiatric diagnosis, and duration of hospital stay.
Psychosocial measures
Information related to psychosocial factors such as support from family, perceived stigma accruing from HIV status, and discrimination from society was collected. Further, questions about perceived memory deficits in the past month which might have interfered with daily functioning were assessed by questions such as “Do you experience frequent memory loss?”, “Do you feel you are slower when reasoning or solving problems?”, and “Do you have difficulties in paying attention?” (15).
The International HIV dementia scale (IHDS)
The International HIV dementia scale (IHDS) (16) was used to screen for HIV-associated neurocognitive disorder or HIV dementia. This tool has been validated in different African and Caucasian populations and has been shown to have a sensitivity of 88% and 80% and specificity scores of 50% and 55% respectively (16-17). The tool measures three essential components of neurological impairments: these include cognition, motor, and psychomotor deficits. Each component has a maximum score of 4, with a total score of three components summing to 12 (16). Any value of less than 10 is indicative of neurocognitive deficits, and patients receiving such a score are referred for further psychiatric follow-up by higher referral hospital (16). The IHDS does not require proficiency in the English language and is ideal for measuring probable HAND in people living with HIV.
Statistical analysis
Data were analyzed using the Statistical Package for the Social Sciences (SPSS), version 21 (SPSS Inc., Chicago, IL). Bivariate correlation and Chi-square tests were used to determine the correlation between the independent variables and probable HAND status; those sociodemographic, clinical and psychosocial risk factors with a p-value of less than 0.25 were selected for the multivariate association analysis with the outcome measure. Binary logistic regression was used to assess the multivariate association between the dependent variable, i.e., HAND status and independent variables. Models were adjusted for age, gender, education, marital status, severity of illness (hospital stay) and stigma (indirectly related to increased anxiety and depression) towards people living with HIV. A Mann Whitney test was performed to assess the difference between the mean scores of participants in the probable HIV dementia group and the non-demented group.
Logistic regression was applied after verifying all its assumptions in the study data. In general, the dependent variable, namely, HAND status was measured as a dichotomous variable. Second, there was independence of observations as assessed by the Durbin Watson test. No outlier was found, as assessed by Mahalanobis Distances for multivariate outliers and box plot analysis for univariate outliers. Independent variables (continuous) were linearly related to log odds as determined by the absence of significance for the interaction effect. Additionally, the study data also satisfied the minimum sample size requirement. Based on the present prevalence of 41% for HAND, the sample size calculation for 9 independent variables included in the model and the expected probability of the least frequent outcome being .10, it was determined that a minimum sample size of (10*9/.4) =90/.4=225 was needed.