Bo Bengtsson

Bio: Bo Bengtsson is an academic researcher from Lund University. The author has contributed to research in topics: Glaucoma & Population. The author has an hindex of 21, co-authored 39 publications receiving 6322 citations. Previous affiliations of Bo Bengtsson include Malmö University & Uppsala University.

Reduction of intraocular pressure and glaucoma progression: results from the Early Manifest Glaucoma Trial.

Abstract: Objective To provide the results of the Early Manifest Glaucoma Trial, which compared the effect of immediately lowering the intraocular pressure (IOP), vs no treatment or later treatment, on the progression of newly detected open-angle glaucoma. Design Randomized clinical trial. Participants Two hundred fifty-five patients aged 50 to 80 years (median, 68 years) with early glaucoma, visual field defects (median mean deviation, −4 dB), and a median IOP of 20 mm Hg, mainly identified through a population screening. Patients with an IOP greater than 30 mm Hg or advanced visual field loss were ineligible. Interventions Patients were randomized to either laser trabeculoplasty plus topical betaxolol hydrochloride (n = 129) or no initial treatment (n = 126). Study visits included Humphrey Full Threshold 30-2 visual field tests and tonometry every 3 months, and optic disc photography every 6 months. Decisions regarding treatment were made jointly with the patient when progression occurred and thereafter. Main Outcome Measures Glaucoma progression was defined by specific visual field and optic disc outcomes. Criteria for perimetric progression were computer based and defined as the same 3 or more test point locations showing significant deterioration from baseline in glaucoma change probability maps from 3 consecutive tests. Optic disc progression was determined by masked graders using flicker chronoscopy plus side-by-side photogradings. Results After a median follow-up period of 6 years (range, 51-102 months), retention was excellent, with only 6 patients lost to follow-up for reasons other than death. On average, treatment reduced the IOP by 5.1 mm Hg or 25%, a reduction maintained throughout follow-up. Progression was less frequent in the treatment group (58/129; 45%) than in controls (78/126; 62%) ( P =.007) and occurred significantly later in treated patients. Treatment effects were also evident when stratifying patients by median IOP, mean deviation, and age as well as exfoliation status. Although patients reported few systemic or ocular conditions, increases in clinical nuclear lens opacity gradings were associated with treatment ( P = .002). Conclusions The Early Manifest Glaucoma Trial is the first adequately powered randomized trial with an untreated control arm to evaluate the effects of IOP reduction in patients with open-angle glaucoma who have elevated and normal IOP. Its intent-to-treat analysis showed considerable beneficial effects of treatment that significantly delayed progression. Whereas progression varied across patient categories, treatment effects were present in both older and younger patients, high- and normal-tension glaucoma, and eyes with less and greater visual field loss.

Factors for glaucoma progression and the effect of treatment: the early manifest glaucoma trial.

Abstract: Objective: To assess factors for progression in the Early Manifest Glaucoma Trial (EMGT), including the effect of EMGT treatment. Setting/Participants: Two hundred fifty-five open-angle glaucoma patients randomized to argon laser trabeculoplasty plus topical betaxolol or no immediate treatment (129 treated; 126 controls) and followed up every 3 months. Methods: Progression was determined by perimetric and photographic optic disc criteria. Patient-based risk of progression was evaluated using Cox proportional hazard regression models and was expressed as hazard ratios (HR) with 95% confidence intervals (95% CI). Results: After 6 years, 53% of patients progressed. In multivariate analyses, progression risk was halved by treatment (HR=0.50; 95% CI, 0.35-0.71). Predictive baseline factors were higher intraocular pressure (IOP) (ie, the higher the baseline IOP, the higher the risk), exfoliation, and having both eyes eligible (each of the latter 2 factors doubled the risk), as well as worse mean deviation and older age. Progression risk decreased by about 10% with each millimeter of mercury of IOP reduction from baseline to the first follow-up visit (HR=0.90 per millimeter of mercury decrease; 95% CI, 0.86-0.94). The first IOP at that visit (3 months' follow-up) was also related to progression (HR=1.11 per millimeter of mercury higher; 95% CI, 1.06-1.17), as was the mean IOP at follow-up (HR=1.13 per millimeter of mercury higher; 95% CI, 1.07-1.19). The percent of patient follow-up visits with disc hemorrhages was also related to progression (HR=1.02 per percent higher; 95% CI, 1.01-1.03). No other factors were identified. Conclusions: Patients treated in the EMGT had half of the progression risk of control patients. The magnitude of initial IOP reduction was a major factor influencing outcome. Progression was also increased with higher baseline IOP, exfoliation, bilateral disease, worse mean deviation, and older age, as well as frequent disc hemorrhages during follow-up. Each higher (or lower) millimeter of mercury of IOP on follow-up was associated with an approximate 10% increased (or decreased) risk of progression.

Measuring visual field progression in the Early Manifest Glaucoma Trial.

Abstract: . Aims: The Early Manifest Glaucoma Trial (EMGT) (316 eligible eyes) has used a new set of criteria to define visual field progression in glaucoma. This paper provides estimates of the amount of visual field worsening required to reach the EMGT definition of definite perimetric progression. Methods: In the 148 eyes that reached definite progression, we first determined changes between baseline and the time of definite EMGT progression, both for mean deviation (MD) and for number of highly (p < 0.5%) significantly depressed test points in pattern deviation probability maps. Second, we studied whether such changes depended on baseline MD, intraocular pressure (IOP), age and time to progression, all of which are factors that affect the rate of field progression. Results: In eyes reaching progression, the mean change in MD from baseline was −1.93 dB (SE ± 0.20) and the mean change in number of significant points was +4.85 (SE ± 0.35). These changes did not show linear dependency on baseline MD, IOP or time to progression. Conclusions: The average amount of field deterioration needed to reach EMGT visual field progression has been measured and expressed in more conventional units (i.e. a loss of about − 2dB in MD and an increase in about five highly significant points). These estimates will facilitate the clinical interpretation of the results of EMGT.

Factors for progression and glaucoma treatment: The Early Manifest Glaucoma Trial.

Abstract: Purpose of reviewThis review summarizes factors for progression in the Early Manifest Glaucoma Trial (EMGT), including the effect of treatment. EMGT randomized patients with early glaucoma either to argon laser trabeculoplasty plus betaxolol (n = 129) or to no immediate treatment (n = 126) and follo

Reduction of intraocular pressure and glaucoma progression: results from the Early Manifest Glaucoma Trial.

Abstract: Objective To provide the results of the Early Manifest Glaucoma Trial, which compared the effect of immediately lowering the intraocular pressure (IOP), vs no treatment or later treatment, on the progression of newly detected open-angle glaucoma. Design Randomized clinical trial. Participants Two hundred fifty-five patients aged 50 to 80 years (median, 68 years) with early glaucoma, visual field defects (median mean deviation, −4 dB), and a median IOP of 20 mm Hg, mainly identified through a population screening. Patients with an IOP greater than 30 mm Hg or advanced visual field loss were ineligible. Interventions Patients were randomized to either laser trabeculoplasty plus topical betaxolol hydrochloride (n = 129) or no initial treatment (n = 126). Study visits included Humphrey Full Threshold 30-2 visual field tests and tonometry every 3 months, and optic disc photography every 6 months. Decisions regarding treatment were made jointly with the patient when progression occurred and thereafter. Main Outcome Measures Glaucoma progression was defined by specific visual field and optic disc outcomes. Criteria for perimetric progression were computer based and defined as the same 3 or more test point locations showing significant deterioration from baseline in glaucoma change probability maps from 3 consecutive tests. Optic disc progression was determined by masked graders using flicker chronoscopy plus side-by-side photogradings. Results After a median follow-up period of 6 years (range, 51-102 months), retention was excellent, with only 6 patients lost to follow-up for reasons other than death. On average, treatment reduced the IOP by 5.1 mm Hg or 25%, a reduction maintained throughout follow-up. Progression was less frequent in the treatment group (58/129; 45%) than in controls (78/126; 62%) ( P =.007) and occurred significantly later in treated patients. Treatment effects were also evident when stratifying patients by median IOP, mean deviation, and age as well as exfoliation status. Although patients reported few systemic or ocular conditions, increases in clinical nuclear lens opacity gradings were associated with treatment ( P = .002). Conclusions The Early Manifest Glaucoma Trial is the first adequately powered randomized trial with an untreated control arm to evaluate the effects of IOP reduction in patients with open-angle glaucoma who have elevated and normal IOP. Its intent-to-treat analysis showed considerable beneficial effects of treatment that significantly delayed progression. Whereas progression varied across patient categories, treatment effects were present in both older and younger patients, high- and normal-tension glaucoma, and eyes with less and greater visual field loss.

The Ocular Hypertension Treatment Study: baseline factors that predict the onset of primary open-angle glaucoma.

Abstract: Background The Ocular Hypertension Treatment Study (OHTS) has shown that topical ocular hypotensive medication is effective in delaying or preventing the onset of primary open-angle glaucoma (POAG) in individuals with elevated intraocular pressure (ocular hypertension) and no evidence of glaucomatous damage. Objective To describe baseline demographic and clinical factors that predict which participants in the OHTS developed POAG. Methods Baseline demographic and clinical data were collected prior to randomization except for corneal thickness measurements, which were performed during follow-up. Proportional hazards models were used to identify factors that predicted which participants in the OHTS developed POAG. Results In univariate analyses, baseline factors that predicted the development of POAG included older age, race (African American), sex (male), larger vertical cup-disc ratio, larger horizontal cup-disc ratio, higher intraocular pressure, greater Humphrey visual field pattern standard deviation, heart disease, and thinner central corneal measurement. In multivariate analyses, baseline factors that predicted the development of POAG included older age, larger vertical or horizontal cup-disc ratio, higher intraocular pressure, greater pattern standard deviation, and thinner central corneal measurement. Conclusions Baseline age, vertical and horizontal cup-disc ratio, pattern standard deviation, and intraocular pressure were good predictors for the onset of POAG in the OHTS. Central corneal thickness was found to be a powerful predictor for the development of POAG.

The Pathophysiology and Treatment of Glaucoma: A Review

Abstract: Importance Glaucoma is a worldwide leading cause of irreversible vision loss. Because it may be asymptomatic until a relatively late stage, diagnosis is frequently delayed. A general understanding of the disease pathophysiology, diagnosis, and treatment may assist primary care physicians in referring high-risk patients for comprehensive ophthalmologic examination and in more actively participating in the care of patients affected by this condition. Objective To describe current evidence regarding the pathophysiology and treatment of open-angle glaucoma and angle-closure glaucoma. Evidence Review A literature search was conducted using MEDLINE, the Cochrane Library, and manuscript references for studies published in English between January 2000 and September 2013 on the topics open-angle glaucoma and angle-closure glaucoma. From the 4334 abstracts screened, 210 articles were selected that contained information on pathophysiology and treatment with relevance to primary care physicians. Findings The glaucomas are a group of progressive optic neuropathies characterized by degeneration of retinal ganglion cells and resulting changes in the optic nerve head. Loss of ganglion cells is related to the level of intraocular pressure, but other factors may also play a role. Reduction of intraocular pressure is the only proven method to treat the disease. Although treatment is usually initiated with ocular hypotensive drops, laser trabeculoplasty and surgery may also be used to slow disease progression. Conclusions and Relevance Primary care physicians can play an important role in the diagnosis of glaucoma by referring patients with positive family history or with suspicious optic nerve head findings for complete ophthalmologic examination. They can improve treatment outcomes by reinforcing the importance of medication adherence and persistence and by recognizing adverse reactions from glaucoma medications and surgeries.