Human Immunodeficiency Virus (HIV) is a public health problem all over the world. Anti-Retroviral Therapy is one of the main ways of controlling infections with HIV. Excellent adherence to ART is essential to avoid the development of resistance; hence, treatment should not be interrupted [1]. Adherence to antiretroviral therapy is a powerful predictor of survival for individuals living with HIV and Acquired Immunodeficiency Syndrome (AIDS) [2]. If adherence to Anti-retrovirals (ARVs) is not kept above 90%, HIV can develop mutations that lead to drug resistance. This makes first line ARVs ineffective thereby worsening the epidemic.

According to Rabkin and colleagues [3], missing even a few doses of ARV treatment a week risks viral resistance and treatment failure; and may be worst in the long run than taking no medication at all. The quality of care and adherence to ARV treatment has witnessed a decline in follow up and an increase in defaulting [4].

Mobile phones are becoming ever more important in African nations particularly in the health context where they have increased the efficiency of service delivery to the poor [5]. In Yaounde, Cameroon, studies by Rougemont and co-workers [6] indicated that care delivery to people living with HIV and AIDS could be improved through the use of cellphones using Short Message Services (SMS). Data for 2010 showed that globally, over 33.3 million people (up from 28.6 million in 2001) were living with HIV giving a prevalence of 0.8 % and 5,254,000 people were on ARV treatment giving an ARV coverage of 36% [7]. By the end of 2010, 34 million people worldwide were living with HIV and AIDS.

In Sub-Saharan Africa, over 22.5 million people (prevalence of 5.0%) were infected with the virus and over 3.9 million of them were on ARV treatment [7]. In 2009, 610,000 people were living with HIV in Cameroon [8] and 76,228 people were on ARV. In 2010, 249,341 people were eligible for HIV treatment in Cameroon but only 88,589 people were on ARVs. By June 2011, according to the National AIDS Control Committee [9], the number of people on ARVs in Cameroon was 97,418.

When patients are not closely monitored right from the initial stage, some may be lost to follow up. The Cameroon Ministry of Public Health [10] revealed that out of the 37,081 patients on treatment by the end of June 2007, only 34,788 came back at the end of September 2007. About 6.2% of the patients (2,293) dropped out of active treatment during this quarter [10]. The HIV prevalence in Cameroon is 5.1% with regional variations but the North West Region had the highest prevalence of 8.6% in 2010 [11].

Many studies have been carried out to measure adherence using various approaches such as self-reports, clinical assessments, pill counts, drug refills, directly observed therapy, and biological assays among others. This study was undertaken to assess the usefulness of cellphone text messages to improve the adherence of HIV and AIDS patients to their treatment and care in the North West Region of Cameroon.

Participants included 45 PLWHIV in the intervention group and 45 PLWHIV in the control group. The demographic characteristics of the participants are shown in Table 1.

The number of times patients missed treatment for one month in each study arm is shown in Fig. (2). The association between the treatment duration and ARV adherence is shown in Table 2. However, two patients could not provide complete information on treatment duration and adherence to ARVs. Out of the 40 respondents who defaulted treatment, 13 (32.5%) had been on treatment only for one year, and 10 (25.0%) only for two years.

Fig. (2). Number of times patients missed treatment for one month in each study arm.

Reasons why patients missed treatment are shown in Table 3. Some of the reasons why people do not belong to support groups (Table 4) accounted for some of the factors that contribute to non-adherence to ARVs as shown in Table 3. From Table 4, 11(12.2%) patients could not provide any reason for non-adherence to ARVs. Coming back home late or unable to respect medication schedule (45%), travelling out of station without medication (17.5%) and forgetfulness (22.5%) were the most prominent reasons why people missed taking their drugs.

From Table 4, majority [29 (36.7%)] of respondents in both the intervention and control groups were not aware of the existence of support groups, 21 (26.6%) were very busy, while 10 (12.7%) indicated they were still to join. Some said they did not want to join while others said they did not have the money to register into support groups, 5 (6.3%) and 6 (7.6%) respectively.

The results obtained from the intervention arm of the study about SMSs revealed the following information as presented in Table 5. More than half [26 (57.8%)] of the respondents who received SMSs indicated that the messages were good and wished that they should continue. Of all responses, 9 (20%) of the respondents indicated that they were very happy because the messages were encouraging. Also, 9 (20%) of the respondents indicated that the messages gave them psycho-social support. Proposals sought from patients to improve treatment and care is presented in Table 6. From Table 6, 25 (28.4%) participants wished that drug refill (appointments for drug refills) should be done every two months rather than every one month. Out of this number, 10 were in the intervention group and 15 were in the control group. Of the 45 respondents who received SMS messages, 15 (17%) wished that SMS messages should be sent to their phones throughout the treatment period. Thirteen (14.8%) of the respondents (5 in the intervention arm and 8 in the control arm) wished that the cost of CD4⁺ T cell count test be reduced and 11 (12.5%) of the respondents indicated that the center should always have drugs available for patients. Though 8 (9.1%) of the respondents indicated that they were satisfied with the present care that they were receiving, 4 (4.5%) indicated that delay time at the clinic should be reduced as much as possible.

All the 45 respondents who received SMSs in their phones acknowledged that these messages were useful for their treatment and care. The various ways by which respondents of the intervention arm felt about the effects of SMSs are shown in Table 7.

Of the 45 respondents, 28 (62.2%) took their treatment regularly and on time because of the reminder SMSs, 7 (15.6%) were able to respect their appointment day and 4 (8.9%) indicated that they were now aware of the importance of CD4⁺ T cell count test in their treatment and care. The overall key findings of the study after the SMS interventions in both arms are shown in Table 8. A Comparison of the level of adherence to ARVs in baseline data with the intervention and control groups as shown in Table 9. The results in Tables 8, 9 indicate that SMSs have improved the treatment and care of people living with HIV and AIDS.

Patients who were married missed their treatment more often than those who were not as 54.17% of patients who missed their treatment were married. Married patients may be more involved with family responsibilities that are likely to interfere with their adherence to ARVs. Also, failing to respect drug refill appointments was observed more in the control group as opposed to the intervention group. Similar results were obtained by Rougemont and co-workers [6] where 30% of participants failed to return for drug refill. Failing to refill drugs implies interruption in treatment which contributes to poor adherence. It was demonstrated that people with a lower level of education missed their treatment many more times as compared to those with higher levels of education. This falls in line with findings by Kalichman and associates [15] that people with higher levels of health literacy adhere better to their medication.

The study revealed that there were a number of factors associated with missing treatment which directly impacted on adherence. These factors in the control group included coming home late, unavailability of drugs, forgetfulness, getting up late, and travelling without taking drugs along, as opposed to the situation in the intervention group where the factors included coming back home late, being very busy and travelling without taking drugs along (p=0.00).

The study showed that being involved in outdoor business is a factor that significantly contributes to non- adherence to ARVs as 60.87% of those who were involved in outdoor business missed their treatment. This suggests that the busy nature of those involved in business rendered them more likely to miss their treatment. The findings also revealed that ARVs were not always available for patients at the treatment center as only 78.4% of patients received their drugs whenever they went for drug refill. This has been confirmed by Eboko [16]. If drugs are not always available, adequate adherence of > 90% cannot be attained and so resistance to ARVs may likely develop. This has been confirmed by Mills and colleagues [2] who showed that HIV can develop mutations if adherence is not kept above 90%. Other studies [3, 17- 19] have showed that some of these factors were demonstrated to be associated with missing treatment and consequently poor adherence.

This study demonstrated that patients showed a significant level of acceptance of the cellphone SMSs strategy for their treatment and care. It revealed that 57% of patients who received the messages actually expressed the wish for the strategy to continue. By implication, these messages, if well targeted, will serve as reminders to respect treatment time, drug refill appointments and other laboratory investigations which will increase adherence and improve on the quality of care.

Looking at the effects of SMSs, results revealed that 28 (62.22%) of patients were able to take their treatment regularly and on time while 15.56% of the patients were actually reminded of their appointment day for drug refill. These findings are in conformity with the study carried out in Uganda by Chang and colleagues [20]. Other findings have also demonstrated that SMSs have a modifying effect on some of the drug related practices by patients [21, 22]. Of the 12 patients who were initially on traditional medication alongside ARVs, 7(58.3%) abandoned it after the intervention. Information self-reported by patients showed that SMSs sent to them, were successful in dissuading patients from taking traditional medication alongside ARVs.

The study is important because it improved adherence to ARVs and revealed some factors that contributed to non-adherence which, if targeted through SMSs, will continue to increase adherence and consequently reduce treatment failure, hence, improving the quality of life of HIV and AIDS patients.

With a constant struggle to improve on the quality of care, innovative approaches such as the use of cellphone SMSs for the care of people living with HIV and AIDS (adherence in intervention = 64.4% while adherence in control group = 44.2%) would motivate patients to be more involved and committed to their treatment and care.

Despite the efforts by the health system to provide quality treatment and care, and reduce treatment failure, there are a number of individual, system and environmental factors that impinge on adherence to ARV treatment. These factors which included forgetfulness, unavailability of ARVs, busy work schedule, and travelling without drugs, need to be addressed at the level of all treatment centers to ensure good adherence.

The use of cellphone SMSs in the care of people living with HIV and AIDS is a strategy that is accepted by patients, given that it is non-invasive. However, it will be cost effective to institute this strategy on a large scale.

NDS designed the study, oversaw data collection and supervised the work, participated in data analysis, drafted the manuscript and substantially revised it for academic content; LI conducted the study, performed the analysis and drafted the manuscript; NFP oversaw data collection and supervised the work and substantially revised the manuscript for academic content. JCNA and TEA participated in data collection, drafted the manuscript and substantially revised it for academic content. All authors read and approved the final copy of the manuscript.

The authors confirm that this article content has no conflict of interest.