204 Diabetes Mellitus
parasympathetic and sympathetic innervation of the corpora
cavernosa (Watkins & Thomas, 1998). Penile erection, a vas-
cular event under neurogenic control, is dependent on relax-
ation of the smooth muscle cells and arteries of the corpus
cavernosum (Bloomgarden, 1998). Animal research with
male Wistar rats has demonstrated that GHb impairs corpora
cavernosal smooth muscle relaxation, and this effect is dose
dependent (Cartledge, Eardley, & Morrison, 2000), suggest-
ing a role for hyperglycemia in ED. Sexually dysfunctional
diabetic men may also experience reduced tactile sensitivity
and altered perception of stimulation (Morrissette, Goldstein,
Raskin, & Rowland, 1999).
No studies have focused exclusively on the role of
glycemic control in the risk of developing sexual complica-
tions in diabetes (Herter, 1998). However, the relationship
between glycemic control and risk of neuropathy is clearly
established for type 1 diabetes (DCCT, 1993) and has been
suggested in type 2 diabetes as well (Toyry, Niskanen, Man-
tysaari, Lansimies, & Uusitupa, 1996). Thus, if neuropathy
can be prevented by glycemic control, sexual dysfunction,
mediated by hyperglycemia in diabetes mellitus, may also be
prevented (Herter, 1998).
Treatment options include both invasive (e.g., penile pros-
thesis implants, intracavernous injection therapy) and non-
invasive (e.g., vacuum device) medical and psychosocial
interventions (e.g., sex therapy; Watkins & Thomas, 1998).
More recently, oral agents such as sildena“l citrate have been
introduced with success in men with types 1 and 2 diabetes,
regardless of age, duration of ED, and duration of diabetes
(Rendell et al., 1999).
Sexual Dysfunction in Women with Diabetes
The research on sexual dysfunction in women with diabetes
is limited and lags behind that of male sexuality. The existing
research is characterized by methodological limitations and
variations and contradictory results, which makes it dif“cult
to interpret the “ndings.
Findings on the prevalence and correlates of sexual desire
in these women range from no difference in the number of
complaints between diabetes patients and healthy controls
(Kolodny, 1971) to signi“cantly decreased desire (Schreiner -
Engel, Schiavi, Vietorisz, Eichel, & Smith, 1985). Some have
found sexual desire de“cits limited to women with neuro-
pathy (Leedom, Feldman, Procci, & Zeidler, 1991) or type 2
diabetes (Schreiner-Engel, Schiavi, Vietorisz, & Smith,
1987). Thus, it is not clear that women with diabetes experi-
ence dif“culties with sexual desire at rates dissimilar from
the general population. The objective assessment of arousal
is more dif“cult in women (Enzlin et al., 1998); therefore,
studies have used questionnaires or self-reported subjective
arousal, and these “ndings suggest that arousal may be a con-
cern for women with diabetes (Schreiner-Engel et al., 1985).
Because of a weak correlation between genital and subjective
arousal, recent studies have included objective assessments
of arousal such as labiothermometry or vaginal plethysmog-
raphy (Enzlin et al., 1998; Spector et al., 1993), but these
“ndings are also equivocal (Wincze, Albert, & Bansal, 1993).
With respect to the orgasm phase, research “ndings are again
contradictory and range from signi“cantly reduced or gasmic
responses in women with diabetes compared to controls
(Schreiner-Engel et al., 1987), no decrease (Montenero,
Donatoni, & Magi, 1973), or failure to specify orgasmic dif-
“culties as a concern (Jensen, 1981). Rates of dyspareunia, a
recurrent or persistent genital pain with sexual intercourse,
appear similar to those found in the general population
(Spector et al., 1993). However, Schreiner-Engel et al. (1985)
found higher rates in women with type 2 diabetes than in
controls.
In women, the role of organic etiologic factors is not as
clear or well understood as in men (Cox, Gonder-Frederick, &
Saunders, 1991). Although diabetic autonomic neuropathy is
believed to be a major cause of organic impotence in men,
evidence for a relationship between neuropathy and sexual
dysfunction in women is unclear (Spector et al., 1993). Based
on the limited research to date, microvascular disease,
nephropathy, retinopathy, macrovascular disease, age of
onset, duration, and glycemic control tend not to be associ-
ated with sexual dysfunction in female diabetes patients
(Campbell, Redelman, Borkman, McLay, & Chisholm, 1989;
Jensen, 1986). The few studies that included psychosocial
factors, such as marital satisfaction (Schreiner-Engel et al.,
1985), disease acceptance (Jensen, 1986), and depression
(Leedom et al., 1991), have found relationships between
poorer psychosocial adjustment and sexual functioning
in these women. In one of the few studies comparing types of
diabetes, type 2 diabetes was predictive of sexual dysfunction
(Schreiner-Engel et al., 1987), which the authors attribute
to the later age of onset of this type of diabetes. Treatment
of sexual dysfunction in women has also received little recog-
nition in the literature. Interventions typically focus on
dif“culties with arousal and lubrication, with recommenda-
tions of diversi“cation of sexual behaviors/positions and
use of lubricating products.SummaryThe research on sexual dysfunction in diabetes has focused
predominantly on men and has supported an organic etiology
(autonomic neuropathy) for the primary form of dysfunction,