|
|
| |
Research
project
Dr
Amanda Patterson
BSc, MND, PhD
|
|
|
Doctoral
Thesis: Iron deficiency
in women of childbearing age
utilisation among women in Australia
Supervisors: Professor
Wendy Brown & Professor David Roberts
University: Research
Centre for Gender and Health, The University of Newcastle
The current prevalence of iron deficiency for Australian
women of childbearing age is unknown, but baseline data
from the Australian Longitudinal Study of Women's Health
(ALSWH) suggest that one in three women have had diagnosed
iron deficiency by the age of 45-50 years. Despite this,
dietary and lifestyle factors which are important in the
development of iron deficiency have not yet been clearly
defined for Australian women, and the public health impact
of this condition remains unclear. In addition, while
the Australian Iron Status Advisory Panel (AISAP) currently
recommends dietary intervention as the first line of treatment
for iron deficiency in adults, the efficacy of dietary
treatment has not been evaluated. The thesis resulting
from this PhD research describes a series of studies which
examine the development, implications and treatment of
iron deficiency for Australian women of childbearing age.
A detailed literature review provides background information
on the physiology of iron, the biochemical and haematological
variables used to assess iron status, and the current
definitions used for the diagnosis of iron deficiency.
Iron deficiency has been shown to adversely affect work
performance, immunity, thermoregulation and cognitive
functioning, and the research describing these relationships
is reviewed. Dietary and lifestyle factors thought to
be important determinants of iron status, and the current
strategies used in the prevention and treatment of iron
deficiency are also discussed.
The PhD work included two preliminary studies. The first
was a general practitioner (GP) survey and pathology audit
which examined the knowledge, attitude and behaviour of
GPs in relation to the diagnosis and treatment of iron
deficiency. While diagnosis practices were generally in
accordance with AISAP recommendations, treatment practices
were not. Supplementation was the preferred treatment
option in even mild cases of iron deficiency, and this
preference may reflect the poor dietary knowledge of GPs
in relation to enhancers and inhibitors of iron absorption.
The second preliminary study was an epidemiological analysis
of baseline and follow-up data from the ALSWH to determine
the impact of self-reported iron deficiency on general
health and well-being (measured using the Short Form-36
General Health and Well-being questionnaire; SF-36) for
two large cohorts of Australian women. Baseline and longitudinal
analysis of these data showed reduced vitality and physical
and mental health for women who reported iron deficiency.
The major component of this research was a randomised
control trial which compared dietary and supplement treatment
for iron deficiency. Baseline dietary, lifestyle and morbidity
data were examined for iron deficient and iron replete
women. Multivariate analyses were used to investigate
the relative importance of dietary and lifestyle factors
in the development of iron deficiency for women of childbearing
age. Iron status was positively associated with oral contraceptive
pill use and alcohol consumption and negatively associated
with phytate intake. The effects of iron deficiency on
general health and well-being, fatigue and cognitive functioning
were examined using the SF-36 general health questionnaire,
the Piper Fatigue Scale and four sub-scales of Wechsler
Adult Intelligence Scale-Revised (WAIS-R), respectively.
Iron deficiency was associated with decreased mental health,
vitality and cognitive functioning, and increased fatigue
in the baseline data.
Dietary and supplement treatment for iron deficiency and
the relative effects of each on general health and well-being,
fatigue and cognitive functioning were compared. Both
dietary and supplement treatment resulted in significant
improvements in haemoglobin and serum ferritin, but changes
in serum ferritin were seen more quickly for the supplement
group. Women in both the diet and the supplement intervention
groups showed significant improvements in general health
and well-being, fatigue and cognitive functioning during
the trial. Improvements in mental health were more marked
among women in the diet intervention group, while vitality
and fatigue improved similarly for women in both groups.
Women in both groups also improved similarly on two sub-scales
of the WAIS-R which assess reasoning and perceptual organisation.
From this research it is clear that women who suffer from
iron deficiency experience major morbidity in terms of
vitality, fatigue and general health and well-being. Dietary
intakes of alcohol and phytate have been highlighted as
possible factors in the determination of iron status,
and dietary treatment of iron deficiency has been shown
to be effective.
|
|
|
|