Iron status and factors influencing iron status of Solomon Islands women living in New Zealand : a thesis presented in the partial fulfillment of the requirements for the degree of Masters of Science (Human Nutrition), Massey University, Albany, New Zealand

Abstract

Iron deficiency is a global problem among women of reproductive age, particularly in developing countries. A recent survey from the Solomon Islands reported that 44% of women of reproductive aged were anaemic. Currently nothing is known about the iron status of women from the Solomon Islands living in New Zealand (NZ).

Aim: This study aims to assess and compare iron status and factors influencing iron status of Solomon Islands with Caucasian women living in and around Auckland, NZ.

Methods: This was a cross-sectional study comparing 40 Solomon Islands women with 80 age-matched Caucasian women living in and around Auckland. Serum ferritin (SF), C-reactive protein (CRP) and haemoglobin (Hb) were analyzed. Iron status was defined as: iron replete (SF > 20 µg/L + Hb > 120 g/L), iron deficiency (ID) (SF < 20 µg/L + Hb > 120 g/L) and iron deficiency anaemia (IDA) (SF < 20 µg/L + Hb < 120 g/L). Participants with CRP >10 mg/L were excluded from this study. Dietary assessment was conducted using a computerised iron food frequency questionnaire including questions on dietary habits, purposely to assess foods affecting iron status. In addition, a 24-hour dietary recall was used to assess the average daily nutrient intake of Solomon Islands women. Demographic and body composition data were also collected together with data on other factors affecting iron status such as blood loss and general health history.

Results: No significant difference in the prevalence of low iron stores + IDA was found in Solomon Islands and Caucasian women (17 vs. 23%, p=0.478). The frequency of red meat, prepared meat and offal, and all white meat consumption did not differ between the two groups (p=0.187). There was a significant difference in fish/seafood consumption (p=0.001), Solomon Islands women consumed fish/seafood more frequently than Caucasian women. Solomon Islands women also consumed medium-high vitamin C fruits more frequently (p=0.002) and dairy products less frequently (p=0.001) than Caucasian women. No significant difference (p=0.872) was identified in the frequency of intake of beverages containing polyphenol between the two groups. But the analysis of individual beverages showed that Solomon Islands women more frequently consumed black tea compared to Caucasian women, the similar practice was identified from the dietary habit assessment where 40% of Solomon Islands women drank black tea an hour before or after evening meals. Fewer Solomon Islands women consumed multivitamins/minerals than Caucasian women (12.8% vs. 66.7% respectively) and none of the Solomon Islands women reported taking dietary supplements compared to 44% Caucasian women. In regards to menstrual blood loss, although there was no significant difference between the two groups in overall menstrual blood loss units, Caucasian women reported on average 1 day longer menstrual period than Solomon Islands women. A small number of women in each group had previously donated blood, but in every case it had taken place more than 6 months prior to this study. Contraceptive use was significantly lower among Solomon Islands women compared to Caucasian women (p=0.001). Body mass index and waist circumferences were significantly higher (p=0.001 and p=0.001 respectively) in the Solomon Islands women compared to the Caucasian women.

Conclusion: The iron status of Solomon Islands and Caucasian women did not differ, but there was variability between groups in the intake of foods and behaviours that are known to influence iron status. This study found both protective and non-protective factors for ID among Solomon Islands women, although the correlation of those factors with iron status were not able to be assessed due to a relatively small sample size and low prevalence of ID/IDA. This study therefore concludes that ID was not a concern for Solomon Islands women living in NZ, and that the prevalence was lower in this group than in women living in the Solomon Islands. This is possibly the result of adapting to different dietary habits and behaviours, increased accessibility to animal sources of iron, and high intakes of vitamin C-rich foods in their host country.