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Undernutrition continues to affect many children below the age of five years in low- and middle income countries. Stunting, also commonly referred as linear growth faltering or retardation, is
the most prevalent manifestation of undernutrition compared to wasting and underweight. A
global reduction in the prevalence of undernutrition has been reported albeit regional variations.
The number of stunted children is increasing steadily in sub-Saharan Africa. The 2010 Tanzania
Demographic Health Survey showed unacceptably high levels of stunting, wasting and
underweight among children below the age of five years; 42.0%, 4.8% and 15.8%, respectively.
Children below the age of three years, children in rural areas and those living in the southern and
central regions of the country were the most affected. Consequences of undernutrition during the
formative years include poor growth, increased risk of and prolonged morbidity, mortality,
delayed cognitive and motor development. Promotion of optimal feeding, health and growth
during the first two years of life is a matter of immediate concern. Interventions to improve
feeding and nutrition of infants during this period include promotion of breastfeeding,
communication and education on complementary feeding behaviours, provision of food
supplements, single and multiple micronutrients supplementation, reduction of diseases through
appropriate hygiene practices, management and treatment of severe acute malnutrition. Reviews
of previous interventions have reported that interventions with an educational component can
effectively improve complementary feeding behaviours, dietary intake and child growth. There is
limited information on the implementation and evaluation of evidence- and theory-based,
culturally appropriate nutrition education interventions to improve diets and growth of rural
infants in Tanzania.
The aim of this thesis was to: 1) characterise dietary and growth patterns of infants and young
children living in rural Tanzania, and 2) develop and evaluate the effectiveness of a nutrition
education package on feeding practices, dietary adequacy and growth of infants and young
children in rural Tanzania. It was hypothesised that the nutrition education package would
improve feeding practices, dietary adequacy and growth as compared to the routine health
education given at health facilities. To accomplish these objectives, the research was organised
into two studies: two cross-sectional studies to establish the nutrition- and health-related
problems in a rural area and guide decisions on improvement, and an intervention study to
improve dietary practices and growth.
A cross-sectional survey involving 496 infants (age 1-12 months) was conducted in six villages of
Mpwapwa district in 2009 (Chapter 2). The study assessed feeding practices and nutritional status
of children, and determined the macronutrient and selected micronutrient contents in commonly consumed complementary meals. Implications for dietary adequacy and nutritional status of the
studied children are reported. The same cohort of infants (n=374, age 9-20 months) was revisited in 2010 to evaluate progress in their nutritional status after the first survey. Results of the 2009
survey showed that mean age of introduction of complementary foods (3.30±1.45) was earlier
than the recommended age of six months. Porridge was the main complementary meal and the
porridge samples contained relatively high water content, increasing the likelihood of reduced
nutrient content. Mean number of meals consumed including snacks were lower than the age specific World Health Organization recommendations. There was limited inclusion of nutrient dense foods (e.g. legumes, animal-source foods, vegetables) in the meals. Small meal portion
sizes, limited variety and the generally low nutrient content of meals increased the risk of not
meeting the recommended nutrients intakes. Prevalence of stunting in 2009 and 2010 was 33.5%
and 59.3%, respectively. Morbidity due to acute respiratory illness (ARI) was 63.9% in 2009 and
56.4% in 2010. Diarrhoea affected 48.4% children in 2009 and 36.4% in 2010 Overall prevalence
of anaemia was 36.1% in 2009 and 36.7% in 2010. Results of the cross-sectional surveys
demonstrated a need for a nutrition intervention to improve dietary practices, health and growth
in infants and young children in rural Tanzania. While interventions to improve feeding, health and
growth exist, it is imperative that they are contextualised to enhance feasibility and sustainability.
Intervention Mapping and Theory of Planned Behaviour provided systematic frameworks for the
design, development and evaluation of a nutrition education package (Chapter 3). The package
had three components: 1) education, counselling and cooking demonstration with mothers, 2)
training of village health workers (VHW) to counsel mothers and family members during monthly
home visits, and 3) supervision of the trained village health workers. Training and education
materials were also developed for respective participants. A cluster randomised controlled trial
was implemented for six months in Mpwapwa district to evaluate the effectiveness of the
package. Eighteen villages were randomly allocated to either routine health education (control,
n=9) or nutrition education package (intervention, n=9). Routine health education is a standard
government health service for children below the age of five years, offered monthly by health staff
at health facilities. It offers education to mothers during growth monitoring and immunisation
contacts. The sessions are usually short (10-15 minutes) and focus on general health issues
including child feeding, prevention of diseases such as malaria and importance of immunisations.
Primary outcome was length-for-age Z-scores. Secondary outcomes included weight, weight-for length Z-scores, intakes of energy, fat, iron and zinc from complementary foods, meal frequency
and dietary diversity. A process evaluation was also carried out to provide insights into the nature
of the processes leading to intervention effectiveness or ineffectiveness.
A total of 370 infants aged 6-7 months (control: n=186; intervention: n=184) participated in the
intervention trial starting December 2014. Findings of the trial are presented in Chapter 4. At
baseline, inadequate feeding practices and nutrient intake, morbidity, anaemia and poor growth
were widespread. After intervention, mean change in feeding frequency was modestly higher in
the intervention than control group (1.63 vs. 1.27, p=0.051). Mean change in dietary diversity was significantly higher in intervention than control group (2.03 vs. 1 50, p=0.005). Infants in the
intervention group had higher intakes of energy (+43.8 kcal, p=0.019) and fat (+2.7g, p=0.033)
than infants in the control group. No effect was observed for iron and zinc intakes. The
intervention resulted in significant mean change in length (0 47cm, 95% Cl: 0.01, 0.92, p=0.043)
and length-for-age Z-scores (0.20 Z-score, 95% Cl: 0.29, 0.38, p=O.O22) in intervention compared
with the control group. The intervention had no differential effects on mean changes in weight,
weight-for-length and weight-for age Z-scores.
Chapter 5 presents results of the process evaluation. Fidelity, recruitment, reach, dose and
contextual factors were reported for each package component. The package components and
elements (training VHW, education and cooking demonstration with mothers, home visits,
supervision of VHW) were implemented across the intervention villages as planned. The
intervention was well received with good dose and was well accepted by VHW, mothers and their
families. VHW knowledge on IYCF increased significantly during the two training sessions (I'1
session: +5.7-point, p<0.001; 2nd session: +4.1-point, p=0.003). Between midtrial and end of trial,
the majority of mothers tried the promoted recipes at home (89.8% and 94.6%) and some tried all
the recommended feeding and health practices (37.7% and 66.1%) Barriers to adoption of the
recommended practices included high maternal workload, cultural beliefs on feeding choices and
inadequate household income. Chapter 6 discusses the implications of the findings and
recommendations for further research.
In conclusion, this PhD research demonstrated that inadequate dietary practices and poor
nutrition are consistently widespread in infants and young children in rural settings. Further, the
nutrition education package adds to the evidence that practical nutrition education incorporating
cooking demonstrations and regular home visits can improve feeding practices, dietary intake of
macronutrients and growth, better than the routine health education delivered at health facilities.
Child health status, socio-cultural and household factors played a significance role in influencing
intervention outcomes. Barriers to intervention effects included high infant morbidity, high
maternal workload, inadequate household income and mothers' habitual and cultural influences
on feeding choices. The research calls for a review of routine health education for the delivery of
quality nutrition services and improvement of child health services for reducing morbidity burden.
There is also a need for joint strategies with other sectors (e.g. agriculture-livestock production,
marketing-roads infrastructure, income generation initiatives) to address the underlying causes of
child undernutrition. |
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