0.3. Utilidad de la investigación
1.2.7. Lenguajes de programación y paradigmas
morbidity and public health sector expenditures.94 As shown below in Figure 4,
cardiovascular disease is the highest ranking cause of death in the country, accounting for
33% of deaths annually.97 Heart disease, cancer, and diabetes together account for 63% of
all T&T deaths.97 NCDs are strongly influenced by four main behavioural risk factors:
tobacco use, insufficient physical activity, harmful use of alcohol, and unhealthy diet.98
These lead to a myriad of common physical, psychological, and lifestyle conditions such as diabetes, obesity, dyslipidaemias, hypertension and these, in turn, are risk factors of sexual dysfunction.99
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Figure 4: Proportional mortality [all ages + sexes]World Health Organization: Non-communicable Diseases (NCD) Country Profiles, 201897
In recent years, pairing of public health priorities, sexual and reproductive health (SRH), and NCDs emerged. This initiative was commenced by the United Nations (UN) in 2011 when they identified several parallels between NCDs and disorders in SRH, including common risk factors, comorbidities and poor health-related quality of life (HRQoL)
caused by them both.100,101 SRH problems can be numerous and refer to any combination
of physiological or psychological issues related to sexuality, sexual dysfunctions, sexual disorders, reproductive concerns or problems. For the scope of this thesis, the focus of SRH will be sexual problems in older adults, primarily sexually transmitted infections (STIs), and aspects of sexual dysfunction exacerbated by the effects of normal ageing. Sexual dysfunction (at any age) refers to the inability of a person to experience sexual desire, arousal, orgasm or satisfaction under normal circumstances, during any stage of sexual activity.102,103,104 According to the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5), difficulties due to sexual dysfunction, excluding those that are substance or medication-induced, cause extreme distress and interpersonal strain for at least 6 months.102,103,104 As a result, sexual dysfunction can have a profound impact
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Sexual dysfunction is a risk factor for vascular dysfunction independent of, but exacerbated by NCD related risk factors.99,105 Normally, for effective sexual arousal in men(penile engorgement and erection) and women, the body must have healthy cellular, vascular, and neurological systems. Together they ensure the release of nitric oxide (NO) from endothelial cells and neurons to initiate vasodilatation to the genitals.99 Vascular
dysfunction from ageing also manifests as endothelial dysfunction which is the basis of other arteriogenic vascular disorders seen in NCDs such as CVDs, CHDs including
ischemic heart disease and diabetes.106 There is evidence to suggest that ED (male sexual
dysfunction) may be associated with atherosclerotic vascular disease, peripheral vascular
disease, hypertension or myocardial infarction (MI).107 Sexual dysfunction, whether
triggered by ageing or NCDs, affect both males and females by decreasing sexual performance, negatively affecting their body image and perceived sexual desirability, lower libido and physical tolerance for sexual activity.99,107 Sexual dysfunction increases
with age as evidence shows it is four-fold higher in men in their 60s.108 For this reason, in
persons 45 years and older, where natural decline in sexual performance may already be
apparent, this can be exacerbated if they have increased risk factors for NCDs as well.109
Cardiovascular Diseases (CVDs), Chronic Heart Disease (CHD)
CVDs/CHDs affect sexual arousal pathways and cause erectile failure in men and lack of vasodilation in women due to endothelial cell dysfunction.109 In light of these parallels
between CVDs/CHDs and impotence, a merger of sexual health and NCD prevention and care clinics could be of benefit as it is possible for a patient with undiagnosed NCDs to present with impotence. This may be indicative of a lack of blood flow in other blood vessels and possibly a red flag for heart disease.110 Also, there is evidence that men with
ED have a two-fold increased risk for acute myocardial infarction (AMI).106 The risk of
AMI escalates with ageing. Evidence suggests that men 55 years and older with ED have a four-fold increased risk of AMI.108,111,112 The highest rates of ischemic heart disease and
total CHD mortality for both males and females are seen in the English-speaking Caribbean, Argentina, Canada, the United States (US), and Uruguay; with Trinidad and -
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Hypertension
Hypertension is a contributory risk factor for CHD, 50% of ischemic strokes,
haemorrhagic strokes and sexual dysfunction.99 Hypertension causes phenotypical
modifications of vascular endothelium, leading to endothelial dysfunction. This precedes the development of adverse cardiovascular events and sexual dysfunction. According to the results of the Chronic Risk Factor Survey conducted in 2011 by the MoH of T&T, 1 in 4 persons in T&T is living with high blood pressure. This prevalence is high with approximately twenty-six per cent of the population (29.8% of males and 23.1% of females) known to have this condition.113 This disease is seen in all age groups in T&T but usually in persons with other NCDs or NCD risk factors. If uncontrolled, hypertension in younger males and females increases their risk of sexual dysfunction exponentially with
age.111 This can be compounded by additional risks attributed to other NCDs.
Diabetes Mellitus & Metabolic Syndrome
Diabetes mellitus is one of the most common NCDs in nearly all countries. The global prevalence of diabetes worldwide since 2010 was 285 million and the projection was by 2030 to affect 438 million people. However, the prevalence was already 425 million in 2017,114, 115 and there is a new prediction for diabetes prevalence to rise to 629 million by
2045.116 T&T shows a trend like that of other high-income countries (shown in Figure 5
by the red line in the distribution) that have growing populations over 60 years of age exhibiting the highest proportion of diabetes prevalence.117
Diabetes has been associated with sexual dysfunction both in males and in females.118 It
is an established risk factor for sexual dysfunction in men. Generally, 1 in 10 men present with ED, but it is three times more likely in diabetic men.119,120 Fifty per cent of diabetic men have ED and this proportion increases with age, duration of diabetes, and
deteriorating metabolic control: 39% at age 40, 65% over the age of 65.121 The severity of
ED was found to be associated with increased levels of HbA1c – a long-term measure of blood glucose control. Diabetic men with ED are also at high risk of coronary heart disease.109
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Figure 5: Prevalence of Diabetes in Trinidad & Tobago in adults by ageSource: IDF Diabetes Atlas, 7th Edition, 2015117
The prevalence of sexual dysfunction is also high in diabetic women and more prevalent with age and low-grade education.99,106 Evidence from a 25-year longitudinal study on
sexuality in diabetic women revealed that sexual complications can include reduced sexual arousal, slow and/or inadequate lubrication, diminished sexual desire, and painful sexual intercourse.122 Similar to diabetes, the metabolic syndrome (MetS) is a multifaceted condition with interrelated factors including insulin resistance, central adiposity, dyslipidaemias, low-grade inflammation, and atherosclerotic disease, endothelial dysfunction, and in males low testosterone levels, with the latter three directly related to
sexual dysfunction.123 Patients with uncontrolled diabetes mellitus or MetS have greater
risk for a poorer sexual health-related quality of life, especially if they are in middle or old age.
Smoking
Tobacco is an additional risk factor for ED.124 Trinidad and Tobago has the highest
population of smokers in the English-speaking Caribbean (27%).94 A two- to three-fold
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increased risk of sexual dysfunction has been found in smokers regardless of age.124 The
evidence suggests that men who smoke more than 1 pack per day have a 50% higher chance of impotency than non-smokers of the same age.94 Additionally, the association of
ED with certain risk factors, such as heart disease and hypertension, and those with
CVD/CHD or diabetes was amplified in current cigarette smokers.124,125In women, recent
studies have failed to demonstrate the risk of sexual difficulties among female smokers but infer there is a possibility of nicotine dependence, rather than smoking that might be associated with lower libido.126
Cancer
After cancer treatment, some patients have reported loss of sexual desire, ED in men, and
pain during sexual activity in women as their primary sexual problems.127 Cancer
treatments may impact or cause direct damage to any of the physiological systems needed for a healthy sexual response.128 These may include hormonal, vascular, neurologic,
psychological elements of sexual function or even removal of parts of the reproductive
organs.128 Prostate, bladder, colon, or rectum cancers and those that affect organs in the
pelvis, put survivors at risk of sexual dysfunction. Men treated for prostate cancer have been found to have inevitably higher rates of dysfunction up to 75 - 85 %.128
Obesity & Metabolic Syndrome
Obesity is associated with elevated levels of pro-inflammatory cytokines and C-reactive protein (CRP). These result in endothelial dysfunction and hypogonadism.129 Evidence from a longitudinal study on middle-aged men found that sexual functioning is also affected by body mass index (BMI) and abnormal lipid profile, predictors of erectile
dysfunction (ED) 25 years later.130,131 Being overweight or obese may increase the risk of
ED by 30–90% as compared with persons of normal weight.130 Subjects with ED tend to
be heavier and with a greater waist than subjects without ED, and are also more likely to be hypertensive and hypercholesterolemic. In T&T, the prevalence of obesity in 2016 was 18.6%.132 This is significant even though for this research it is uncertain what percentage is attributed to persons in middle and old age.
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1.3.1.3.2 Current Priorities for the Management of NCDs in T&TThe Ministry of Health (MoH) has a functional Chronic Disease Assistance Programme (CDAP) that provides citizens with free prescription drugs and other pharmaceuticals for treatment but for a prescribed list of chronic conditions including diabetes, asthma, cardiac diseases, arthritis, glaucoma, mental depression, high blood pressure, benign prostatic
hyperplasia, epilepsy, Parkinson’s disease, and thyroid diseases.133 Although medications
are available to assist the management of chronic illness in the middle-aged and older population alleviating some of the risk factors for sexual dysfunction and ED, some of
these very same medications are pharmacological instigators for sexual dysfunction.134
Sexual health problems for older adults are an emerging public health concern.135 These
problems already occur through normal ageing but may generate much more distress for those living with comorbidities from NCDs.162 In addition to the risks for sexual
dysfunction, ageing does not spare older adults from the risks of contracting sexually transmitted infections (STIs), like their younger counterparts. NCDs and ageing are not the only factors impacting on sexual dysfunction but STIs as well.136 According to Laumann et al. (2008), in the US National Social Life, Health and Ageing project (NSHAP) study, anyone with a lifetime history of STIs, will have increased odds of reporting sexual dysfunction problems.137