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804 PA R T V / Health Promotion and Disease Prevention

and glomerular capillary pressures to accelerate nephrosclerosis.
While the presence of macroalbuminuria (proteinuria 300 Table 35-2 ■ CLASSIFICATION OF HYPERTENSIVE
mg/day), indicates presence of kidney disease, even lower level RETINOPATHY
microalbuminuria (30 to 300 mg/day) is associated with increased Retinopathy
cardiovascular risk. Grade Description Systemic Associations*
CKD mandates more aggressive treatment and lower target
BP: 130/80 mm Hg in patients with diabetes or CKD and None No detectable signs None
7
120/75 mm Hg in patients with proteinuria 1 g/day. Anti- Mild One or more of the follow- Modest association with
hypertensive drugs classes differ in ability to lower proteinuria and ing signs: Generalized ar- risk of clinical stroke,
teriolar narrowing, focal
subclinical stroke, coro-
slow the progression of CKD. Drugs that block the rennin– arteriolar narrowing, ar- nary heart disease, and
angiotensin system, that is, angiotensin-converting enzyme (ACE) teriovenous nicking, death
inhibitors and angiotensin receptor blockers (ARBs), are the most opacity (“copper wiring”)
potent antiproteinuric agents and also have been shown to be Moderate Hemorrhage (blot, dot, or Strong association with risk
flame-shaped), microa-
of clinical stroke,
highly effective in slowing the progression of renal insufficiency. 58 neurysm, cotton–wool subclinical stroke, cogni-
spot, hard exudate, or a tive decline, and death
Eye. HTN has profound effects on the structure and function
combination of these from cardiovascular
of the eye. Hypertensive retinopathy refers to a spectrum of mi- signs causes
crovascular signs in the retina related to HTN. 59 HTN initially Malignant Signs of moderate retinopa- Strong association with
causes retinal circulation vasospasm and increased vasomotor tone, thy plus swelling of the death
which are reflected as the sign of generalized arteriolar narrowing. optic disk †
Persistent HTN leads to arteriosclerotic changes, including intimal
thickening, media wall hyperplasia, and hyaline degeneration. This *A modest association is defined as an odds ratio of greater than 1 but less
than 2. A strong association is defined as an odds ratio of 2 or greater.
is seen as increasingly severe generalized arteriolar narrowing, arte- † Anterior ischemic optic neuropathy, characterized by unilateral swelling of
riolar wall opacification, and focal narrowing. Thickening of the the optic disk, visual loss, and sectorial visual field loss, should be ruled out.
retinal arteriolar wall by these arteriosclerotic processes may com- From Wong, T. Y., & Mitchell, P. (2004). Hypertensive retinopathy. New
press the venules, resulting in the sign of AV nicking. In the pres- England Journal of Medicine, 351, 2310–2317.
ence of more acute elevations in BP, an exudative stage may occur,
manifesting as microaneurysms, hemorrhages, hard exudates, and
cotton wool spots. Optic disk swelling and macular edema may
cephalopathy is a consequence of accelerated or malignant HTN.
occur with severely elevated BP. These processes may not occur in
Encephalopathy occurs when the BP levels exceed the upper limit
the sequence described above. Numerous studies have confirmed
of autoregulation so that the cerebral arteries become dilated, dis-
the strong association between the presence of signs of hyperten- rupting the blood–brain barrier and leading to the formation of
59
sive retinopathy and elevated BP. The strongest evidence of the
cerebral edema; local changes in ion and cytokine concentrations;
usefulness of the evaluation of hypertensive retinopathy for risk 65
and/or alteration in neural function.
stratification is based on its association with stroke as the retinal
circulation shares anatomical, physiological, and embryologic fea-
tures with the cerebral circulation. A simplified classification of MANAGEMENT OF HTN
hypertensive retinopathy—none, mild, moderate, and malig-
nant—according to the severity of the retinal signs is presented in Assessment and Diagnosis
Table 35-2. 59
Diagnosis
Brain. HTN has adverse consequences in the brain, including HTN is relatively easy to diagnose. However, in part due to the
ischemia and hemorrhagic stoke, cognitive impairment/dementia, lack of symptoms, an individual may not seek evaluation or treat-
and encephalopathy. HTN contributes to the development of ath- ment of HTN. In fact, more than 30% of the hypertensive pop-
erosclerotic plaques in the extracerebral and intracranial vessels as ulation in the United States are unaware of their condition. The
3
well as the process of microatheroma and hypertensive hyalinosis. awareness, treatment, and control rates for HTN in the United
Despite the brain’s adaptive mechanisms to maintain cerebral blood States between 1999 and 2004 are shown in Table 35-3. While the
flow, loss or reduction of blood flow results in stroke producing 37% HTN control rate in 2004 demonstrates continued im-
pathologic changes related to the duration and degree of ischemia. provement, it also clearly indicates a need for increased efforts on
Research has documented the positive relationships between the part of health care professionals to better manage the treat-
stroke and HTN as well as the reduction in stroke with HTN ment of HTN. 3
control. 5,60–63
Cognitive impairment spans the spectrum from mild cognitive BP Measurement. Accurate BP measurement is essential to
impairment to dementia. Cerebrovascular damage leading to cog- classify individuals, to ascertain BP-related risk, and to guide
66
nitive impairment can occur not only from atherothrombosis but HTN management. Proper training of observers, positioning of
also through cerebral hemorrhage, hypoperfusion, and other arte- the patient, and selection of cuff size are all essential. Because an
riopathies. Longitudinal studies strongly suggest an adverse effect of individual’s BP can vary markedly, diagnosis of HTN requires
elevated BP in middle age on cognitive functioning. 64 There is documentation of elevated BP (average of two or more BPs) on at
also an adverse effect of low BP in the older adults for develop- least three separate occasions. Three measures of BP potentially
ment of dementia; however, studies suggest no deterioration in could contribute to the adverse effects of HTN. The first is the av-
cognitive performance with antihypertensive therapy in older erage level, the second is the diurnal variation, and the third is the
adults hypertensive individuals who are well. Hypertensive en- short-term variability. The measure of BP that is most clearly related