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Abstract Abdominal aortic aneurysm (AAA) can be defined as an abdominal aortic diameter of 3.0 cm in either anteriorposterior or transverse planes. Prevalence rates of AAA vary according to age, gender and geographical location. Important risk factors for AAA are advanced age, male gender, smoking and a positive family history for AAAs. (Schlo¨sser et al.,2008) The reported average growth rate of AAAs between 3.0 and 5.5 cm ranges from 0.2 to 0.3 cm per year. Larger AAA diameters are associated with higher AAA growth rates. (Schlo¨sser et al.,2008) A wide variation between patients has been reported consistently. Smoking cessation may be recommended to reduce the rate of AAA growth. Larger initial aneurysm diameter is a significant and independent risk factor for AAA rupture. (Schlo¨sser et al.,2008) Other factors that have been associated with an increased risk of AAA rupture include female gender, smoking and hypertension. Population screening of older men for AAA, in regions where the population prevalence is 4% or more, reduces aneurysm-related mortality by almost half within 4 years of screening, principally by reducing the incidence of aneurysm rupture. Screening only smokers might improve the cost-effectiveness of aneurysm screening. (Vega et al.,2006) Population screening of older women for AAA may not reduce the incidence of aneurysm rupture. Population screening of older female smokers for AAA may require further investigation. Screening of older men and women having a family history of AAA might be recommended. Opportunistic screening of patients with peripheral arterial disease should be considered. The screening model chosen should be flexible for the local population characteristics. Men should be screened with a single scan at 65 years old. Screening should be considered at an earlier age for those at higher risk for AAA. Repeat screening should be considered only in those initially screened at a younger age or at higher risk for AAA. (Vega et al.,2006) Screening programmes should be well advertised and tailored to the local population to maximise attendance. Invitation to screening from the general or family practitioner might be received favourably. Incidental pathology should be referred to the family practitioner. If screening programmes use relatively inexperienced screening staff and portable ultrasound devices, programmes should be audited for quality control. (Solberg et al.,2005) Screen detection of an AAA causes a small but temporary reduction in quality of life. Aneurysm screening should only be conducted if the audited mortality from aneurysm repair at the referral hospital is low. Referral hospital facilities must be in place before AAA screening starts to cope with an increased number of elective AAA repairs, both open and endovascular. (Vega et al.,2006) All subjects with a screen-detected aneurysm should be referred for cardiovascular risk assessment with concomitant advice and treatment, including statins and smoking cessation therapy. Rescreening intervals should shorten as the aneurysm enlarges. (Solberg et al.,2005) When the threshold diameter (5.5 cm, measured by ultrasonography, in males) is reached or symptoms develop or rapid aneurysm growth is observed (>1 cm/year), immediate referral to a vascular surgeon is recommended. To prevent interval rupture, it is recommended that a vascular surgeon review patients within 2 weeks of the aneurysm reaching 5.5 cm or more in diameter. In some centres an earlier referral, at between 5.0 and 5.5 cm is an acceptable alternative practice. In-patient management might be considered for aneurysms over 9 cm in diameter. A policy of ultrasonographic surveillance of small aneurysms (4.0e5.5 cm) is safe and advised for asymptomatic aneurysms. (Dalman et al.,2006) Patients with a higher risk of rupture should be considered for surgery when the maximum aortic diameter reaches 5.0 cm. There remains some uncertainty about the management of small aneurysms in defined subgroups (e.g. young patients, females, and those with limited life expectancy). Females should be referred to vascular surgeons for assessment at a maximum aortic diameter of 5.0 cm as measured by ultrasonography, and aneurysm repair should be considered at a maximum aneurysm diameter of 5.2 cm in females. (Dalman et al.,2006) The digit ratio is the ratio of the lengths of different digits or fingers typically measured from the midpoint of bottom crease where the finger joins the hand to the tip of the finger . (Ecker ,2006) It has been suggested by some scientists that the ratio of two digits in particular, the 2nd (index finger) and 4th (ring finger), is affected by exposure to androgens e.g. testosterone while in the uterus and that this 2D:4D ratio can be considered a crude measure for prenatal androgen exposure, with lower 2D:4D ratios pointing to higher androgen exposure. (Ecker ,2006) The 2D:4D ratio is calculated by dividing the length of the index finger of the right hand by the length of the ring finger. A longer index finger will result in a ratio higher than 1, while a longer ring finger will result in a ratio of less than 1. (Hönekopp et al.,2007) The 2D:4D digit ratio is sexually dimorphic: while the second digit is typically shorter in both females and males, the difference between the lengths of the two digits is greater in males than females. (Hönekopp et al.,2007) A number of studies have shown a correlation between the 2D:4D digit ratio and various physical and behavioral traits. (Hönekopp et al.,2007)Digital ration is not studied previously in relation to AAA or other vascular diseases. However, Manning et al found 2D:4D, a putative correlate of prenatal testosterone, is quite strongly predictive of performance in endurance running in both men and women and based on that speculated that the relationship may arise because prenatal testosterone has an organizing effect on the vascular system (Manning et al.,2007). While screening for these cohort groups from Sweden and Egypt, it is interesting to measure 2D:4D to investigate the potential link between 2D:4D ration and AAA and to investigate ethnic susceptibility to AAA in relation to 2D:4D. Thus, exploring the possibility of future use of 2D:4D as a predictive factor to AAA (Manning et al.,2007). |